Copyright © 2015 Bert N. Langford (Images may be subject to copyright. Please send feedback)
Welcome to Our Generation USA!
Science
covers all branches and disciplines of Science.
Click here to be taken to the web page "Modern Medicine"
Click here for "Computer Advancements"
Click here to be taken to the web page "Innovations"
Click here to be taken to the web page "Best of the Internet"
Click here to be taken to the web page "Space Exploration"
Science
YouTube Video: Standing Ovation Stephen Hawking's Lecture
Pictured: A Graph of Science and all of its branches
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.
Contemporary science is typically subdivided into the natural sciences, which study the material world; the social sciences, which study people and societies; and the formal sciences, such as mathematics. The formal sciences are often excluded as they do not depend on empirical observations. Disciplines which use science like engineering and medicine may also be considered to be applied sciences.
During the Middle Ages in the Middle East, foundations for the scientific method were laid by Alhazen in his Book of Optics.
From classical antiquity through the 19th century, science as a type of knowledge was more closely linked to philosophy than it is now and, in fact, in the Western world, the term "natural philosophy" encompassed fields of study that are today associated with science, such as astronomy, medicine, and physics.
While the classification of the material world by the ancient Indians and Greeks into air, earth, fire and water was more philosophical, medieval Middle Eastern scientists used practical, experimental observation to classify materials.
In the 17th and 18th centuries, scientists increasingly sought to formulate knowledge in terms of laws of nature. Over the course of the 19th century, the word "science" became increasingly associated with the scientific method itself, as a disciplined way to study the natural world.
It was in the 19th century that scientific disciplines such as biology, chemistry, and physics reached their modern shapes. The same time period also included the origin of the terms "scientist" and "scientific community," the founding of scientific institutions, and increasing significance of the interactions with society and other aspects of culture.
Click on any of the following Hyperlinks for amplification:
Contemporary science is typically subdivided into the natural sciences, which study the material world; the social sciences, which study people and societies; and the formal sciences, such as mathematics. The formal sciences are often excluded as they do not depend on empirical observations. Disciplines which use science like engineering and medicine may also be considered to be applied sciences.
During the Middle Ages in the Middle East, foundations for the scientific method were laid by Alhazen in his Book of Optics.
From classical antiquity through the 19th century, science as a type of knowledge was more closely linked to philosophy than it is now and, in fact, in the Western world, the term "natural philosophy" encompassed fields of study that are today associated with science, such as astronomy, medicine, and physics.
While the classification of the material world by the ancient Indians and Greeks into air, earth, fire and water was more philosophical, medieval Middle Eastern scientists used practical, experimental observation to classify materials.
In the 17th and 18th centuries, scientists increasingly sought to formulate knowledge in terms of laws of nature. Over the course of the 19th century, the word "science" became increasingly associated with the scientific method itself, as a disciplined way to study the natural world.
It was in the 19th century that scientific disciplines such as biology, chemistry, and physics reached their modern shapes. The same time period also included the origin of the terms "scientist" and "scientific community," the founding of scientific institutions, and increasing significance of the interactions with society and other aspects of culture.
Click on any of the following Hyperlinks for amplification:
Animal Science
YouTube Video What is life - lecture for 1st year Bioscience students
Pictured: Careers in Bioscience
Animal Science (also Animal Bioscience) is described as "studying the biology of animals that are under the control of humankind".
Historically, the degree was called animal husbandry and the animals studied were livestock species, like cattle, sheep, pigs, poultry, and horses. Today, courses available now look at a far broader area to include companion animals like dogs and cats, and many exotic species.
Degrees in Animal Science are offered at a number of colleges and universities. In the United States, the universities offering such a program were Land Grant Universities and include University of Nebraska–Lincoln, Cornell University, UC Davis, Michigan State University, Purdue University, The Ohio State University, The Pennsylvania State University, Iowa State University and the University of Minnesota.
Typically, the Animal Science curriculum not only provides a strong science background, but also hands-on experience working with animals on campus-based farms.
Professional education in animal science prepares students for career opportunities in areas such as animal breeding, food and fiber production, nutrition, animal agribusiness, animal behavior and welfare, and biotechnology. Courses in a typical Animal Science program may include genetics, microbiology, animal behavior, nutrition, physiology, and reproduction.
Courses in support areas, such as genetics, soils, agricultural economics and marketing, legal aspects, and the environment also are offered. All of these courses are essential to entering an animal science profession.
At many universities, a Bachelor of Science (BS) degree in Animal Science allows emphasis in certain areas. Typical areas are species-specific or career-specific. Species-specific areas of emphasis prepare students for a career in dairy management, beef management, swine management, sheep or small ruminant management, poultry production, or the horse industry.
Other career-specific areas of study include pre-veterinary medicine studies, livestock business and marketing, animal welfare and behavior, animal nutrition science, animal reproduction science, or genetics. Youth programs are also an important part of animal science programs.
Many schools that offer a degree option in Animal Science also offer a pre-veterinary emphasis such as the University of Nebraska-Lincoln and the University of Minnesota, for example. This option provides an in-depth knowledge base of the biological and physical sciences including nutrition, reproduction, physiology, and genetics. This can prepare students for graduate studies in animal science, veterinary school, and pharmaceutical or animal science industries.
Click on any of the following Blue Hyperlinks for further amplification:
Historically, the degree was called animal husbandry and the animals studied were livestock species, like cattle, sheep, pigs, poultry, and horses. Today, courses available now look at a far broader area to include companion animals like dogs and cats, and many exotic species.
Degrees in Animal Science are offered at a number of colleges and universities. In the United States, the universities offering such a program were Land Grant Universities and include University of Nebraska–Lincoln, Cornell University, UC Davis, Michigan State University, Purdue University, The Ohio State University, The Pennsylvania State University, Iowa State University and the University of Minnesota.
Typically, the Animal Science curriculum not only provides a strong science background, but also hands-on experience working with animals on campus-based farms.
Professional education in animal science prepares students for career opportunities in areas such as animal breeding, food and fiber production, nutrition, animal agribusiness, animal behavior and welfare, and biotechnology. Courses in a typical Animal Science program may include genetics, microbiology, animal behavior, nutrition, physiology, and reproduction.
Courses in support areas, such as genetics, soils, agricultural economics and marketing, legal aspects, and the environment also are offered. All of these courses are essential to entering an animal science profession.
At many universities, a Bachelor of Science (BS) degree in Animal Science allows emphasis in certain areas. Typical areas are species-specific or career-specific. Species-specific areas of emphasis prepare students for a career in dairy management, beef management, swine management, sheep or small ruminant management, poultry production, or the horse industry.
Other career-specific areas of study include pre-veterinary medicine studies, livestock business and marketing, animal welfare and behavior, animal nutrition science, animal reproduction science, or genetics. Youth programs are also an important part of animal science programs.
Many schools that offer a degree option in Animal Science also offer a pre-veterinary emphasis such as the University of Nebraska-Lincoln and the University of Minnesota, for example. This option provides an in-depth knowledge base of the biological and physical sciences including nutrition, reproduction, physiology, and genetics. This can prepare students for graduate studies in animal science, veterinary school, and pharmaceutical or animal science industries.
Click on any of the following Blue Hyperlinks for further amplification:
- Education
- See also:
- American Registry of Professional Animal Scientists
- Zoology, the interest of all animals.
- Veterinary science
Applied Science
YouTube Video about Applied Science
Pictured: Fields of Applied Science
Applied science is a discipline of science that applies existing scientific knowledge to develop more practical applications, like technology or inventions.
Within natural science, disciplines that are basic science, also called pure science, develop information to predict and perhaps explain—thus somehow understand—phenomena in the natural world. Applied science applies science to real world practice. This includes a broad range of science fields from Engineering to Child Care.
Applied science can also apply formal science, such as statistics and probability theory, as in epidemiology. Genetic epidemiology is an applied science applying both biological and statistical methods.
Branches of applied science
For a topical guide to this subject, see Outline of applied science#Branches of applied science.
Engineering sciences include,
Medical sciences, for instance medical microbiology and its clinical virology, are applied sciences that apply biology toward medical knowledge and inventions, but not necessarily medical technology, whose development is more specifically biomedicine or biomedical engineering.
In Education:
In the United States, The College of William & Mary offers an undergraduate minor as well as Master of Science and Doctor of Philosophy degrees in "applied science." Courses and research cover varied fields including neuroscience, optics, materials science and engineering, nondestructive testing , and nuclear magnetic resonance.
In New York City, the Bloomberg administration awarded the consortium of Cornell-Technion $100 million in City capital to construct the universities' proposed Applied Sciences campus on Roosevelt Island.
See also:
Within natural science, disciplines that are basic science, also called pure science, develop information to predict and perhaps explain—thus somehow understand—phenomena in the natural world. Applied science applies science to real world practice. This includes a broad range of science fields from Engineering to Child Care.
Applied science can also apply formal science, such as statistics and probability theory, as in epidemiology. Genetic epidemiology is an applied science applying both biological and statistical methods.
Branches of applied science
For a topical guide to this subject, see Outline of applied science#Branches of applied science.
Engineering sciences include,
- thermodynamics,
- heat transfer,
- fluid mechanics,
- statics,
- dynamics,
- mechanics of materials,
- kinematics,
- electromagnetism,
- materials science,
- earth sciences,
- engineering physics.
Medical sciences, for instance medical microbiology and its clinical virology, are applied sciences that apply biology toward medical knowledge and inventions, but not necessarily medical technology, whose development is more specifically biomedicine or biomedical engineering.
In Education:
In the United States, The College of William & Mary offers an undergraduate minor as well as Master of Science and Doctor of Philosophy degrees in "applied science." Courses and research cover varied fields including neuroscience, optics, materials science and engineering, nondestructive testing , and nuclear magnetic resonance.
In New York City, the Bloomberg administration awarded the consortium of Cornell-Technion $100 million in City capital to construct the universities' proposed Applied Sciences campus on Roosevelt Island.
See also:
Biology
YouTube Video from the TV Series "Big Bang Theory": Howard, Raj and spider
Pictured: Biology deals with the study of the many living organisms
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, evolution, distribution, identification and taxonomy.
Modern biology is a vast and eclectic field, composed of many branches and sub-disciplines. However, despite the broad scope of biology, there are certain general and unifying concepts within it that govern all study and research, consolidating it into single, coherent field.
In general, biology recognizes the cell as the basic unit of life, genes as the basic unit of heredity, and evolution as the engine that propels the synthesis and creation of new species.
It is also understood today that all the organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition known as homeostasis.
Sub-disciplines of biology are defined by the scale at which organisms are studied, the kinds of organisms studied, and the methods used to study them:
Click on any of the following blue hyperlinks for further amplification:
Modern biology is a vast and eclectic field, composed of many branches and sub-disciplines. However, despite the broad scope of biology, there are certain general and unifying concepts within it that govern all study and research, consolidating it into single, coherent field.
In general, biology recognizes the cell as the basic unit of life, genes as the basic unit of heredity, and evolution as the engine that propels the synthesis and creation of new species.
It is also understood today that all the organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition known as homeostasis.
Sub-disciplines of biology are defined by the scale at which organisms are studied, the kinds of organisms studied, and the methods used to study them:
- biochemistry examines the rudimentary chemistry of life;
- molecular biology studies the complex interactions among biological molecules;
- botany studies the biology of plants;
- cellular biology examines the basic building-block of all life, the cell;
- physiology examines the physical and chemical functions of tissues, organs, and organ systems of an organism;
- evolutionary biology examines the processes that produced the diversity of life;
- and ecology examines how organisms interact in their environment.
Click on any of the following blue hyperlinks for further amplification:
- History
- Foundations of modern biology:
- Cell theory
Evolution
Genetics
Homeostasis
Energy
- Cell theory
- Study and research:
- Structural
- Physiological
Evolutionary
Systematic
Kingdoms
Ecological and environmental
- Basic unresolved problems in biology
- The Main Branches of Biology
- See also:
The Chaos Theory including How to Control Chaos
- YouTube Video Top 10 Most Unhinged Moments on The Office (TV Show)
- YouTube Video: A Humorous Introduction to Chaos Theory with the Lorenz Attractor
- YouTube Video: The Three Types of Chaos in Business
Chaos Theory
Chaos theory is the field of study in mathematics that studies the behavior of dynamical systems that are highly sensitive to initial conditions—a response popularly referred to as the butterfly effect.
Small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for such dynamical systems, rendering long-term prediction impossible in general. This happens even though these systems are deterministic, meaning that their future behavior is fully determined by their initial conditions, with no random elements involved.
In other words, the deterministic nature of these systems does not make them predictable. This behavior is known as deterministic chaos, or simply chaos. The theory was summarized by Edward Lorenz as:
Chaos: When the present determines the future, but the approximate present does not approximately determine the future.
Chaotic behavior exists in many natural systems, such as weather and climate. It also occurs spontaneously in some systems with artificial components, such as road traffic. This behavior can be studied through analysis of a chaotic mathematical model, or through analytical techniques such as recurrence plots and Poincaré maps. Chaos theory has applications in several disciplines, including ___________________________________________________________________________
How to Control Chaos:
In lab experiments that study chaos theory, approaches designed to control chaos are based on certain observed system behaviors.
Any chaotic attractor contains an infinite number of unstable, periodic orbits. Chaotic dynamics, then, consists of a motion where the system state moves in the neighborhood of one of these orbits for a while, then falls close to a different unstable, periodic orbit where it remains for a limited time and so forth. This results in a complicated and unpredictable wandering over longer periods of time.
Control of chaos is the stabilization, by means of small system perturbations, of one of these unstable periodic orbits. The result is to render an otherwise chaotic motion more stable and predictable, which is often an advantage. The perturbation must be tiny compared to the overall size of the attractor of the system to avoid significant modification of the system's natural dynamics.
Several techniques have been devised for chaos control, but most are developments of two basic approaches: the Ott–Grebogi–Yorke (OGY) method and Pyragas continuous control.
Both methods require a previous determination of the unstable periodic orbits of the chaotic system before the controlling algorithm can be designed.
OGY method:
Edward Ott, Celso Grebogi and James A. Yorke were the first to make the key observation that the infinite number of unstable periodic orbits typically embedded in a chaotic attractor could be taken advantage of for the purpose of achieving control by means of applying only very small perturbations.
After making this general point, they illustrated it with a specific method, since called the Ott–Grebogi–Yorke (OGY) method of achieving stabilization of a chosen unstable periodic orbit. In the OGY method, small, wisely chosen, kicks are applied to the system once per cycle, to maintain it near the desired unstable periodic orbit.
To start, one obtains information about the chaotic system by analyzing a slice of the chaotic attractor. This slice is a Poincaré section. After the information about the section has been gathered, one allows the system to run and waits until it comes near a desired periodic orbit in the section.
Next, the system is encouraged to remain on that orbit by perturbing the appropriate parameter. When the control parameter is actually changed, the chaotic attractor is shifted and distorted somewhat.
If all goes according to plan, the new attractor encourages the system to continue on the desired trajectory. One strength of this method is that it does not require a detailed model of the chaotic system but only some information about the Poincaré section. It is for this reason that the method has been so successful in controlling a wide variety of chaotic systems.
The weaknesses of this method are in isolating the Poincaré section and in calculating the precise perturbations necessary to attain stability.
Pyragas method:
Main article: Pyragas method
In the Pyragas method of stabilizing a periodic orbit, an appropriate continuous controlling signal is injected into the system, whose intensity is practically zero as the system evolves close to the desired periodic orbit but increases when it drifts away from the desired orbit.
Both the Pyragas and OGY methods are part of a general class of methods called "closed loop" or "feedback" methods which can be applied based on knowledge of the system obtained through solely observing the behavior of the system as a whole over a suitable period of time.
The method was proposed by Lithuanian physicist Kęstutis Pyragas
Applications:
Experimental control of chaos by one or both of these methods has been achieved in a variety of systems, including:
These attempt the control of chaotic bubbling with the OGY method and using electrostatic potential as the primary control variable.
Forcing two systems into the same state is not the only way to achieve synchronization of chaos. Both control of chaos and synchronization constitute parts of cybernetical physics, a research area on the border between physics and control theory.
See also:
Chaos theory is the field of study in mathematics that studies the behavior of dynamical systems that are highly sensitive to initial conditions—a response popularly referred to as the butterfly effect.
Small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for such dynamical systems, rendering long-term prediction impossible in general. This happens even though these systems are deterministic, meaning that their future behavior is fully determined by their initial conditions, with no random elements involved.
In other words, the deterministic nature of these systems does not make them predictable. This behavior is known as deterministic chaos, or simply chaos. The theory was summarized by Edward Lorenz as:
Chaos: When the present determines the future, but the approximate present does not approximately determine the future.
Chaotic behavior exists in many natural systems, such as weather and climate. It also occurs spontaneously in some systems with artificial components, such as road traffic. This behavior can be studied through analysis of a chaotic mathematical model, or through analytical techniques such as recurrence plots and Poincaré maps. Chaos theory has applications in several disciplines, including ___________________________________________________________________________
How to Control Chaos:
In lab experiments that study chaos theory, approaches designed to control chaos are based on certain observed system behaviors.
Any chaotic attractor contains an infinite number of unstable, periodic orbits. Chaotic dynamics, then, consists of a motion where the system state moves in the neighborhood of one of these orbits for a while, then falls close to a different unstable, periodic orbit where it remains for a limited time and so forth. This results in a complicated and unpredictable wandering over longer periods of time.
Control of chaos is the stabilization, by means of small system perturbations, of one of these unstable periodic orbits. The result is to render an otherwise chaotic motion more stable and predictable, which is often an advantage. The perturbation must be tiny compared to the overall size of the attractor of the system to avoid significant modification of the system's natural dynamics.
Several techniques have been devised for chaos control, but most are developments of two basic approaches: the Ott–Grebogi–Yorke (OGY) method and Pyragas continuous control.
Both methods require a previous determination of the unstable periodic orbits of the chaotic system before the controlling algorithm can be designed.
OGY method:
Edward Ott, Celso Grebogi and James A. Yorke were the first to make the key observation that the infinite number of unstable periodic orbits typically embedded in a chaotic attractor could be taken advantage of for the purpose of achieving control by means of applying only very small perturbations.
After making this general point, they illustrated it with a specific method, since called the Ott–Grebogi–Yorke (OGY) method of achieving stabilization of a chosen unstable periodic orbit. In the OGY method, small, wisely chosen, kicks are applied to the system once per cycle, to maintain it near the desired unstable periodic orbit.
To start, one obtains information about the chaotic system by analyzing a slice of the chaotic attractor. This slice is a Poincaré section. After the information about the section has been gathered, one allows the system to run and waits until it comes near a desired periodic orbit in the section.
Next, the system is encouraged to remain on that orbit by perturbing the appropriate parameter. When the control parameter is actually changed, the chaotic attractor is shifted and distorted somewhat.
If all goes according to plan, the new attractor encourages the system to continue on the desired trajectory. One strength of this method is that it does not require a detailed model of the chaotic system but only some information about the Poincaré section. It is for this reason that the method has been so successful in controlling a wide variety of chaotic systems.
The weaknesses of this method are in isolating the Poincaré section and in calculating the precise perturbations necessary to attain stability.
Pyragas method:
Main article: Pyragas method
In the Pyragas method of stabilizing a periodic orbit, an appropriate continuous controlling signal is injected into the system, whose intensity is practically zero as the system evolves close to the desired periodic orbit but increases when it drifts away from the desired orbit.
Both the Pyragas and OGY methods are part of a general class of methods called "closed loop" or "feedback" methods which can be applied based on knowledge of the system obtained through solely observing the behavior of the system as a whole over a suitable period of time.
The method was proposed by Lithuanian physicist Kęstutis Pyragas
Applications:
Experimental control of chaos by one or both of these methods has been achieved in a variety of systems, including:
- turbulent fluids,
- oscillating chemical reactions,
- magneto-mechanical oscillators
- and cardiac tissues.
These attempt the control of chaotic bubbling with the OGY method and using electrostatic potential as the primary control variable.
Forcing two systems into the same state is not the only way to achieve synchronization of chaos. Both control of chaos and synchronization constitute parts of cybernetical physics, a research area on the border between physics and control theory.
See also:
CERN's Large Hadron Collider
YouTube Video about the CERN Large Hadron Collider
Pictured: LEFT: A section of the Large Hadron Collider; RIGHT: Simulated Large Hadron Collider CMS particle detector data depicting a Higgs boson produced by colliding protons decaying into hadron jets and electrons (Courtesy of Lucas Taylor / CERN - http://cdsweb.cern.ch/record/628469, CC BY-SA 3.0)
The Large Hadron Collider (LHC) is the world's largest and most powerful particle collider, the largest, most complex experimental facility ever built, and the largest single machine in the world.
It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and engineers from over 100 countries, as well as hundreds of universities and laboratories.
It lies in a tunnel 27 kilometres (17 mi) in circumference, as deep as 175 metres (574 ft) beneath the France–Switzerland border near Geneva, Switzerland.
Its first research run took place from 30 March 2010 to 13 February 2013 at an initial energy of 3.5 teraelectronvolts (TeV) per beam (7 TeV total), almost 4 times more than the previous world record for a collider, rising to 4 TeV per beam (8 TeV total) from 2012. On February 13, 2013 the LHC's first run officially ended, and it was shut down for planned upgrades.
'Test' collisions restarted in the upgraded collider on 5 April 2015, reaching 6.5 TeV per beam on 20 May 2015 (13 TeV total, the current world record). Its second research run commenced on schedule, on 3 June 2015.
The LHC's aim is to allow physicists to test the predictions of different theories of particle physics, high-energy physics and in particular, to further test the properties of the Higgs boson and the large family of new particles predicted by supersymmetric theories, and other unsolved questions of physics, advancing human understanding of physical laws.
It contains seven detectors, each designed for certain kinds of research. The proton-proton collision is the primary operation method, but the LHC has also collided protons with lead nuclei for two months in 2013 and used lead–lead collisions for about one month each in 2010, 2011, 2013 and 2015 for other investigations.
The LHC's computing grid was (and currently is) a world record holder. Data from collisions was produced at an unprecedented rate for the time of first collisions, tens of petabytes per year, a major challenge at the time, to be analysed by a grid-based computer network infrastructure connecting 140 computing centers in 35 countries.
By 2012 the Worldwide LHC Computing Grid was also the world's largest distributed computing grid, comprising over 170 computing facilities in a worldwide network across 36 countries.
For further amplification, Click Here
It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and engineers from over 100 countries, as well as hundreds of universities and laboratories.
It lies in a tunnel 27 kilometres (17 mi) in circumference, as deep as 175 metres (574 ft) beneath the France–Switzerland border near Geneva, Switzerland.
Its first research run took place from 30 March 2010 to 13 February 2013 at an initial energy of 3.5 teraelectronvolts (TeV) per beam (7 TeV total), almost 4 times more than the previous world record for a collider, rising to 4 TeV per beam (8 TeV total) from 2012. On February 13, 2013 the LHC's first run officially ended, and it was shut down for planned upgrades.
'Test' collisions restarted in the upgraded collider on 5 April 2015, reaching 6.5 TeV per beam on 20 May 2015 (13 TeV total, the current world record). Its second research run commenced on schedule, on 3 June 2015.
The LHC's aim is to allow physicists to test the predictions of different theories of particle physics, high-energy physics and in particular, to further test the properties of the Higgs boson and the large family of new particles predicted by supersymmetric theories, and other unsolved questions of physics, advancing human understanding of physical laws.
It contains seven detectors, each designed for certain kinds of research. The proton-proton collision is the primary operation method, but the LHC has also collided protons with lead nuclei for two months in 2013 and used lead–lead collisions for about one month each in 2010, 2011, 2013 and 2015 for other investigations.
The LHC's computing grid was (and currently is) a world record holder. Data from collisions was produced at an unprecedented rate for the time of first collisions, tens of petabytes per year, a major challenge at the time, to be analysed by a grid-based computer network infrastructure connecting 140 computing centers in 35 countries.
By 2012 the Worldwide LHC Computing Grid was also the world's largest distributed computing grid, comprising over 170 computing facilities in a worldwide network across 36 countries.
For further amplification, Click Here
Biometrics
YouTube Video: The Key to Security: Biometric Standards
(By the National Institute of Standards and Technology)
Pictured: The block diagram below illustrates the two basic modes of a biometric system. First, in verification (or authentication) mode the system performs a one-to-one comparison of a captured biometric with a specific template stored in a biometric database in order to verify the individual is the person they claim to be. Three steps are involved in the verification of a person:
In the first step, reference models for all the users are generated and stored in the model database.
In the second step, some samples are matched with reference models to generate the genuine and impostor scores and calculate the threshold.
The third step is the testing step. This process may use a smart card, username or ID number (e.g. PIN) to indicate which template should be used for comparison. 'Positive recognition' is a common use of the verification mode, "where the aim is to prevent multiple people from using the same identity".
(Courtesy of Alessio Damato - Own work, CC BY-SA 3.0)
Biometrics refers to metrics related to human characteristics. Biometrics authentication (or realistic authentication) is used in computer science as a form of identification and access control.
It is also used to identify individuals in groups that are under surveillance.
Biometric identifiers are the distinctive, measurable characteristics used to label and describe individuals.
Biometric identifiers are often categorized as physiological versus behavioral characteristics. Physiological characteristics are related to the shape of the body. Examples include, but are not limited to fingerprint, palm veins, face recognition, DNA, palm print, hand geometry, iris recognition, retina and odor/scent.
Behavioral characteristics are related to the pattern of behavior of a person, including but not limited to typing rhythm, gait, and voice. Some researchers have coined the term behaviometrics to describe the latter class of biometrics.
More traditional means of access control include token-based identification systems, such as a driver's license or passport, and knowledge-based identification systems, such as a password or personal identification number.
Since biometric identifiers are unique to individuals, they are more reliable in verifying identity than token and knowledge-based methods; however, the collection of biometric identifiers raises privacy concerns about the ultimate use of this information.
According to a CSO article the biometrics market will be worth US$13.8 billion in 2015.
For Further Amplification, Click Here
Chemistry
YouTube Video from the Big Bang Theory TV Show (CBS): "The Elements" (SIC!)
Pictured: Standard form of the periodic table of chemical elements. The colors represent different categories of elements (Courtesy of DePiep - Own work)
Chemistry is a branch of physical science that studies the composition, structure, properties and change of matter.
Chemistry includes topics such as the properties of individual atoms, how atoms form chemical bonds to create chemical compounds, the interactions of substances through intermolecular forces that give matter its general properties, and the interactions between substances through chemical reactions to form different substances.
Chemistry is sometimes called the central science because it bridges other natural sciences, including physics, geology and biology. For the differences between chemistry and physics see comparison of chemistry and physics.
Scholars disagree about the etymology of the word chemistry. The history of chemistry can be traced to alchemy, which had been practiced for several millennia in various parts of the world.
Click on any of the following for further amplification:
Chemistry includes topics such as the properties of individual atoms, how atoms form chemical bonds to create chemical compounds, the interactions of substances through intermolecular forces that give matter its general properties, and the interactions between substances through chemical reactions to form different substances.
Chemistry is sometimes called the central science because it bridges other natural sciences, including physics, geology and biology. For the differences between chemistry and physics see comparison of chemistry and physics.
Scholars disagree about the etymology of the word chemistry. The history of chemistry can be traced to alchemy, which had been practiced for several millennia in various parts of the world.
Click on any of the following for further amplification:
Industrial Technology
YouTube Video "Industry 4.0 - The Fourth Industrial Revolution"
Picture of the Seven core industrial technology fields that make up "Industry 4.0"
Industrial technology is the use of engineering and manufacturing technology to make production faster, simpler and more efficient.The industrial technology field employs creative and technically proficient individuals who can help a company achieve efficient and profitable productivity.
Industrial Technology programs typically include instruction in optimization theory, human factors, organizational behavior, industrial processes, industrial planning procedures, computer applications, and report and presentation preparation.
Planning and designing manufacturing processes and equipment is a main aspect of being an industrial technologist. An Industrial Technologist is often responsible for implementing certain designs and processes. Industrial Technology involves the management, operation, and maintenance of complex operation systems.
Accreditation and certification:
The USA based Association of Technology, Management, and Applied Engineering (ATMAE), accredits selected collegiate programs in Industrial Technology in the USA. An instructor or graduate of an Industrial Technology program may choose to become a Certified Technology Manager (CTM) by sitting for a rigorous exam administered by ATMAE covering Production Planning & Control, Safety, Quality, and Management/Supervision.
ATMAE program accreditation is recognized by the Council for Higher Education Accreditation (CHEA) for accrediting Industrial Technology programs. CHEA recognizes ATMAE in the U.S. for accrediting associate, baccalaureate, and master's degree programs in technology, applied technology, engineering technology, and technology-related disciplines delivered by national or regional accredited institutions in the United States.(2011)
Knowledge base:
A career in industrial technology typically entails formal education from an accredited college or university. Opportunities are available to professionals with all levels of education. Those who hold associate degrees typically qualify for entry-level technician and technologist positions, such as in the maintenance and operation of machinery. Bachelor's degree-holders could fill management and engineering positions, such as plant manager, production supervisor and quality systems engineer. A graduate degree in industrial technology could qualify individuals for jobs in research, teaching and upper-level management".
Industrial Technology includes wide-ranging subject matter and could be viewed as an amalgamation of industrial engineering and business topics with a focus on practicality and management of technical systems with less focus on actual engineering of those systems.
Typical curriculum at a four-year university might include courses on manufacturing process, technology and impact on society, mechanical and electronic systems, quality assurance and control, materials science, packaging, production and operations management, and manufacturing facility planning and design.
In addition, the Industrial Technologist may have exposure to more vocational-style education in the form of courses on CNC manufacturing, welding, and other tools-of-the-trade in manufacturing.
Industrial Technologist:
Industrial Technology program graduates obtain a majority of positions which are applied engineering and/or management oriented. Since "Industrial Technologist" is not a common job title in the United States, the actual bachelor's degree or associate degree earned by the individual is obscured by the job title he/she receives. Typical job titles for industrial technologists having a bachelor's degree include quality systems engineer, manufacturing engineer, industrial engineer, plant manager, production supervisor, etc. Typical job titles for industrial technologists having a two-year associate degree include project technologist, manufacturing technologist, process technologist, etc.
A technologist curriculum may focus or specialize in a certain technical area of study. Examples of this includes electronics, manufacturing, construction, graphics, automation/robotics, CADD, nanotechnology, aviation, etc.
Technological development in industry:
A major subject of study is technological development in industry. This has been defined as:
Studies in this area often employ a multi-disciplinary research methodology and shade off into the wider analysis of business and economic growth (development, performance). The studies are often based on a mixture of industrial field research and desk-based data analysis and aim to be of interest and use to practitioners in business management and investment (etc.) as well as academics.
In engineering, construction, textiles, food and drugs, chemicals and petroleum, and other industries, the focus has been on not only the nature and factors facilitating and hampering the introduction and utilization of new technologies but also the impact of new technologies on the production organization (etc.) of firms and various social and other wider aspects of the technological development process.
How (and When) Technological development in industry is performed :
Industrial Technology programs typically include instruction in optimization theory, human factors, organizational behavior, industrial processes, industrial planning procedures, computer applications, and report and presentation preparation.
Planning and designing manufacturing processes and equipment is a main aspect of being an industrial technologist. An Industrial Technologist is often responsible for implementing certain designs and processes. Industrial Technology involves the management, operation, and maintenance of complex operation systems.
Accreditation and certification:
The USA based Association of Technology, Management, and Applied Engineering (ATMAE), accredits selected collegiate programs in Industrial Technology in the USA. An instructor or graduate of an Industrial Technology program may choose to become a Certified Technology Manager (CTM) by sitting for a rigorous exam administered by ATMAE covering Production Planning & Control, Safety, Quality, and Management/Supervision.
ATMAE program accreditation is recognized by the Council for Higher Education Accreditation (CHEA) for accrediting Industrial Technology programs. CHEA recognizes ATMAE in the U.S. for accrediting associate, baccalaureate, and master's degree programs in technology, applied technology, engineering technology, and technology-related disciplines delivered by national or regional accredited institutions in the United States.(2011)
Knowledge base:
A career in industrial technology typically entails formal education from an accredited college or university. Opportunities are available to professionals with all levels of education. Those who hold associate degrees typically qualify for entry-level technician and technologist positions, such as in the maintenance and operation of machinery. Bachelor's degree-holders could fill management and engineering positions, such as plant manager, production supervisor and quality systems engineer. A graduate degree in industrial technology could qualify individuals for jobs in research, teaching and upper-level management".
Industrial Technology includes wide-ranging subject matter and could be viewed as an amalgamation of industrial engineering and business topics with a focus on practicality and management of technical systems with less focus on actual engineering of those systems.
Typical curriculum at a four-year university might include courses on manufacturing process, technology and impact on society, mechanical and electronic systems, quality assurance and control, materials science, packaging, production and operations management, and manufacturing facility planning and design.
In addition, the Industrial Technologist may have exposure to more vocational-style education in the form of courses on CNC manufacturing, welding, and other tools-of-the-trade in manufacturing.
Industrial Technologist:
Industrial Technology program graduates obtain a majority of positions which are applied engineering and/or management oriented. Since "Industrial Technologist" is not a common job title in the United States, the actual bachelor's degree or associate degree earned by the individual is obscured by the job title he/she receives. Typical job titles for industrial technologists having a bachelor's degree include quality systems engineer, manufacturing engineer, industrial engineer, plant manager, production supervisor, etc. Typical job titles for industrial technologists having a two-year associate degree include project technologist, manufacturing technologist, process technologist, etc.
A technologist curriculum may focus or specialize in a certain technical area of study. Examples of this includes electronics, manufacturing, construction, graphics, automation/robotics, CADD, nanotechnology, aviation, etc.
Technological development in industry:
A major subject of study is technological development in industry. This has been defined as:
- the introduction of new tools and techniques for performing given tasks in production, distribution, data processing (etc.);
- the mechanization of the production process, or the achievement of a state of greater autonomy of technical production systems from human control, responsibility, or intervention;
- changes in the nature and level of integration of technical production systems, or enhanced interdependence;
- the development, utilization, and application of new scientific ideas, concepts, and information in production and other processes; and
- enhancement of technical performance capabilities, or increase in the efficiency of tools, equipment, and techniques in performing given tasks.
Studies in this area often employ a multi-disciplinary research methodology and shade off into the wider analysis of business and economic growth (development, performance). The studies are often based on a mixture of industrial field research and desk-based data analysis and aim to be of interest and use to practitioners in business management and investment (etc.) as well as academics.
In engineering, construction, textiles, food and drugs, chemicals and petroleum, and other industries, the focus has been on not only the nature and factors facilitating and hampering the introduction and utilization of new technologies but also the impact of new technologies on the production organization (etc.) of firms and various social and other wider aspects of the technological development process.
How (and When) Technological development in industry is performed :
- Technological Processes based always on Material, Equipment, Human skills and operating circumstances.
- So, If any of these parameters changed, we have to re-calibrate this technology to match the designed product.
- This re-calibration can't be considered as a technology change because industrial technology is not more than an Engineering guide to achieve the required specification of the designed product.
- To calibrate any industrial technology, we should make a documented copy of manufacturing experiments until matching the final product specifications based on original technology, new changed parameters and scientific basics.
- Finally, documentation of the new change should be done to the original industrial technology for that new case as a new addition.
- Any application of industrial technology for 1st time or after a long time stop,Technology processes should be tested by a primary samples triers as a Re-calibration process.
Ecology (for conservation need and practices, see "Environment")
YouTube Video: 25 Most Endangered Species On Earth
Pictured below:
LEFT: "The Blue Marble" is a famous photograph of the Earth taken on December 7, 1972, by the crew of the Apollo 17 spacecraft en route to the Moon at a distance of about 29,000 kilometres (18,000 mi). It shows Africa, Antarctica, and the Arabian Peninsula;
CENTER: This is a western toad photographed in a wetland with duckweed:
RIGHT: A Blue Starfish resting on hard Acropora coral. Lighthouse, Ribbon Reefs, Great Barrier Reef.
Ecology is the scientific analysis and study of interactions among organisms and their environment. It is an interdisciplinary field that includes biology, geography, and Earth science.
Ecology includes the study of interactions organisms have with each other, other organisms, and with abiotic components of their environment. Topics of interest to ecologists include the diversity, distribution, amount (biomass), and number (population) of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems.
Ecosystems are composed of dynamically interacting parts including organisms, the communities they make up, and the non-living components of their environment.
Ecosystem processes, such as primary production, pedogenesis, nutrient cycling, and various niche construction activities, regulate the flux of energy and matter through an environment. These processes are sustained by organisms with specific life history traits, and the variety of organisms is called biodiversity. Biodiversity, which refers to the varieties of species, genes, and ecosystems, enhances certain ecosystem services.
Ecology is not synonymous with environment, environmentalism, natural history, or environmental science. It is closely related to evolutionary biology, genetics, and ethology. An important focus for ecologists is to improve the understanding of how biodiversity affects ecological function.
Ecologists seek to explain:
Ecology is a human science as well. There are many practical applications of ecology in,
For example, the Circles of Sustainability approach treats ecology as more than the environment 'out there'. It is not treated as separate from humans. Organisms (including humans) and resources compose ecosystems which, in turn, maintain biophysical feedback mechanisms that moderate processes acting on living (biotic) and non-living (abiotic) components of the planet.
Ecosystems sustain life-supporting functions and produce natural capital like biomass production (food, fuel, fiber, and medicine), the regulation of climate, global biogeochemical cycles, water filtration, soil formation, erosion control, flood protection, and many other natural features of scientific, historical, economic, or intrinsic value.
The word "ecology" ("Ökologie") was coined in 1866 by the German scientist Ernst Haeckel (1834–1919). Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics.
Ancient Greek philosophers such as Hippocrates and Aristotle laid the foundations of ecology in their studies on natural history. Modern ecology became a much more rigorous science in the late 19th century. Evolutionary concepts relating to adaptation and natural selection became the cornerstones of modern ecological theory.
Click on any of the following blue hyperlinks for more about Ecology:
Ecology includes the study of interactions organisms have with each other, other organisms, and with abiotic components of their environment. Topics of interest to ecologists include the diversity, distribution, amount (biomass), and number (population) of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems.
Ecosystems are composed of dynamically interacting parts including organisms, the communities they make up, and the non-living components of their environment.
Ecosystem processes, such as primary production, pedogenesis, nutrient cycling, and various niche construction activities, regulate the flux of energy and matter through an environment. These processes are sustained by organisms with specific life history traits, and the variety of organisms is called biodiversity. Biodiversity, which refers to the varieties of species, genes, and ecosystems, enhances certain ecosystem services.
Ecology is not synonymous with environment, environmentalism, natural history, or environmental science. It is closely related to evolutionary biology, genetics, and ethology. An important focus for ecologists is to improve the understanding of how biodiversity affects ecological function.
Ecologists seek to explain:
- Life processes, interactions, and adaptations
- The movement of materials and energy through living communities
- The successional development of ecosystems
- The abundance and distribution of organisms and biodiversity in the context of the environment.
Ecology is a human science as well. There are many practical applications of ecology in,
- conservation biology,
- wetland management,
- natural resource management (agroecology), agriculture, forestry, agroforestry, fisheries),
- city planning (urban ecology),
- community health,
- economics,
- basic and applied science,
- and human social interaction (human ecology).
For example, the Circles of Sustainability approach treats ecology as more than the environment 'out there'. It is not treated as separate from humans. Organisms (including humans) and resources compose ecosystems which, in turn, maintain biophysical feedback mechanisms that moderate processes acting on living (biotic) and non-living (abiotic) components of the planet.
Ecosystems sustain life-supporting functions and produce natural capital like biomass production (food, fuel, fiber, and medicine), the regulation of climate, global biogeochemical cycles, water filtration, soil formation, erosion control, flood protection, and many other natural features of scientific, historical, economic, or intrinsic value.
The word "ecology" ("Ökologie") was coined in 1866 by the German scientist Ernst Haeckel (1834–1919). Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics.
Ancient Greek philosophers such as Hippocrates and Aristotle laid the foundations of ecology in their studies on natural history. Modern ecology became a much more rigorous science in the late 19th century. Evolutionary concepts relating to adaptation and natural selection became the cornerstones of modern ecological theory.
Click on any of the following blue hyperlinks for more about Ecology:
- Levels, scope, and scale of organization
- Ecological complexity
- Relation to evolution
- Human ecology
- Relation to the environment
- History
- See also:
- Main article: Outline of ecology
- Chemical ecology
- Circles of Sustainability
- Cultural ecology
- Dialectical naturalism
- Ecological death
- Ecological psychology
- Ecology movement
- Ecosophy
- Industrial ecology
- Information ecology
- Landscape ecology
- Natural resource
- Normative science
- Political ecology
- Sensory ecology
- Spiritual ecology
- Sustainable development
- Lists:
Electronics
YouTube Video: Introduction to Basic Electronics
Pictured: Left: Surface-mount electronic components; Right: Hitachi J100 adjustable frequency drive chassis (Picture courtesy of C J Cowie at en.wikipedia - Transferred from en.wikipedia, CC BY-SA 3.0)
Electronics is the science of how to control electric energy, energy in which the electrons have a fundamental role.
Electronics deals with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive electrical components and interconnection technologies.
Commonly, electronic devices contain circuitry consisting primarily or exclusively of active semiconductors supplemented with passive elements; such a circuit is described as an electronic circuit.
The nonlinear behavior of active components and their ability to control electron flows makes amplification of weak signals possible, and electronics is widely used in information processing, telecommunication, and signal processing. The ability of electronic devices to act as switches makes digital information processing possible.
Interconnection technologies such as circuit boards, electronics packaging technology, and other varied forms of communication infrastructure complete circuit functionality and transform the mixed components into a regular working system.
Electronics is distinct from electrical and electro-mechanical science and technology, which deal with the generation, distribution, switching, storage, and conversion of electrical energy to and from other energy forms using wires, motors, generators, batteries, switches, relays, transformers, resistors, and other passive components.
This distinction started around 1906 with the invention by Lee De Forest of the triode, which made electrical amplification of weak radio signals and audio signals possible with a non-mechanical device.
Until 1950 this field was called "radio technology" because its principal application was the design and theory of radio transmitters, receivers, and vacuum tubes.
Today, most electronic devices use semiconductor components to perform electron control. The study of semiconductor devices and related technology is considered a branch of solid-state physics, whereas the design and construction of electronic circuits to solve practical problems come under electronics engineering. This article focuses on engineering aspects of electronics.
For more, click on any of the following Blue Hyperlinks:
Electronics deals with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive electrical components and interconnection technologies.
Commonly, electronic devices contain circuitry consisting primarily or exclusively of active semiconductors supplemented with passive elements; such a circuit is described as an electronic circuit.
The nonlinear behavior of active components and their ability to control electron flows makes amplification of weak signals possible, and electronics is widely used in information processing, telecommunication, and signal processing. The ability of electronic devices to act as switches makes digital information processing possible.
Interconnection technologies such as circuit boards, electronics packaging technology, and other varied forms of communication infrastructure complete circuit functionality and transform the mixed components into a regular working system.
Electronics is distinct from electrical and electro-mechanical science and technology, which deal with the generation, distribution, switching, storage, and conversion of electrical energy to and from other energy forms using wires, motors, generators, batteries, switches, relays, transformers, resistors, and other passive components.
This distinction started around 1906 with the invention by Lee De Forest of the triode, which made electrical amplification of weak radio signals and audio signals possible with a non-mechanical device.
Until 1950 this field was called "radio technology" because its principal application was the design and theory of radio transmitters, receivers, and vacuum tubes.
Today, most electronic devices use semiconductor components to perform electron control. The study of semiconductor devices and related technology is considered a branch of solid-state physics, whereas the design and construction of electronic circuits to solve practical problems come under electronics engineering. This article focuses on engineering aspects of electronics.
For more, click on any of the following Blue Hyperlinks:
- 1 Branches of electronics
- 2 Electronic devices and components
- 3 History of electronic components
- 4 Types of circuits
- 5 Heat dissipation and thermal management
- 6 Noise
- 7 Electronics theory
- 8 Electronics lab
- 9 Computer aided design (CAD)
- 10 Construction methods
- 11 Degradation
- See also:
- Outline of electronics
- Atomtronics
- Audio engineering
- Broadcast engineering
- Computer engineering
- Electronic engineering
- Electronics engineering technology
- Fuzzy electronics
- Index of electronics articles
- List of mechanical, electrical and electronic equipment manufacturing companies by revenue
- Marine electronics
- Power electronics
- Robotics
Engineering
YouTube Video: 10 Greatest Modern Engineering Marvels Of The World
Pictured: Examples of Engineering include:
LEFT: The Ancient Romans built aqueducts to bring a steady supply of clean fresh water to cities and towns in the empire;
CENTER: The International Space Station represents a modern engineering challenge from many disciplines; RIGHT: Hoover Dam
Engineering is the application of mathematics, empirical evidence and scientific, economic, social, and practical knowledge in order to invent, innovate, design, build, maintain, research, and improve structures, machines, tools, systems, components, materials, and processes.
The discipline of engineering is extremely broad, and encompasses a range of more specialized fields of engineering, each with a more specific emphasis on particular areas of applied science, technology and types of application.
Definition:
The American Engineers' Council for Professional Development (ECPD, the predecessor of ABET) has defined "engineering" as:
"The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation or safety to life and property."
History:
Engineering has existed since ancient times as humans devised fundamental inventions such as the wedge, lever, wheel, and pulley. Each of these inventions is essentially consistent with the modern definition of engineering.
The term engineering deriving from the word engineer, which itself dates back to 1300, when an engine'er (literally, one who operates an engine) originally referred to "a constructor of military engines." In this context, now obsolete, an "engine" referred to a military machine, i.e., a mechanical contraption used in war (for example, a catapult).
Notable examples of the obsolete usage which have survived to the present day are military engineering corps, e.g., the U.S. Army Corps of Engineers.
The word "engine" itself is of even older origin, ultimately deriving from the Latin ingenium (c. 1250), meaning "innate quality, especially mental power, hence a clever invention."
Later, as the design of civilian structures such as bridges and buildings matured as a technical discipline, the term civil engineering entered the lexicon as a way to distinguish between those specializing in the construction of such non-military projects and those involved in the older discipline of military engineering.
Disciplines:
Engineering is a broad discipline which is often broken down into several sub-disciplines. These disciplines concern themselves with differing areas of engineering work. Although initially an engineer will usually be trained in a specific discipline, throughout an engineer's career the engineer may become multi-disciplined, having worked in several of the outlined areas. Engineering is often characterized as having four main branches:
Beyond these four, a number of other branches are recognized. Historically, naval engineering and mining engineering were major branches. Other engineering fields sometimes included as major branches are,
New specialties sometimes combine with the traditional fields and form new branches - for example Earth Systems Engineering and Management involves a wide range of subject areas including anthropology, engineering studies, environmental science, ethics and philosophy.
A new or emerging area of application will commonly be defined temporarily as a permutation or subset of existing disciplines; there is often gray area as to when a given sub-field warrants classification as a new "branch." One key indicator of such emergence is when major universities start establishing departments and programs in the new field.
For each of these fields there exists considerable overlap, especially in the areas of the application of fundamental sciences to their disciplines such as physics, chemistry, and mathematics.
Engineers apply mathematics and sciences such as physics to find suitable solutions to problems or to make improvements to the status quo. More than ever, engineers are now required to have knowledge of relevant sciences for their design projects. As a result, they may keep on learning new material throughout their career.
If multiple options exist, engineers weigh different design choices on their merits and choose the solution that best matches the requirements. The crucial and unique task of the engineer is to identify, understand, and interpret the constraints on a design in order to produce a successful result. It is usually not enough to build a technically successful product; it must also meet further requirements.
Constraints may include available resources, physical, imaginative or technical limitations, flexibility for future modifications and additions, and other factors, such as requirements for cost, safety, marketability, productivity, and serviceability. By understanding the constraints, engineers derive specifications for the limits within which a viable object or system may be produced and operated.
A general methodology and epistemology of engineering can be inferred from the historical case studies and comments provided by Walter Vincenti. Though Vincenti's case studies are from the domain of aeronautical engineering, his conclusions can be transferred into many other branches of engineering, too.
According to Billy Vaughn Koen, the "engineering method is the use of heuristics to cause the best change in a poorly understood situation within the available resources." Koen argues that the definition of what makes one an engineer should not be based on what he produces, but rather how he goes about it.
Engineers use their knowledge of science, mathematics, logic, economics, and appropriate experience or tacit knowledge to find suitable solutions to a problem. Creating an appropriate mathematical model of a problem allows them to analyze it (sometimes definitively), and to test potential solutions.
Usually multiple reasonable solutions exist, so engineers must evaluate the different design choices on their merits and choose the solution that best meets their requirements.
Genrich Altshuller, after gathering statistics on a large number of patents, suggested that compromises are at the heart of "low-level" engineering designs, while at a higher level the best design is one which eliminates the core contradiction causing the problem.
Engineers typically attempt to predict how well their designs will perform to their specifications prior to full-scale production. They use, among other things: prototypes, scale models, simulations, destructive tests, nondestructive tests, and stress tests. Testing ensures that products will perform as expected.
Engineers take on the responsibility of producing designs that will perform as well as expected and will not cause unintended harm to the public at large. Engineers typically include a factor of safety in their designs to reduce the risk of unexpected failure. However, the greater the safety factor, the less efficient the design may be.
The study of failed products is known as forensic engineering, and can help the product designer in evaluating his or her design in the light of real conditions. The discipline is of greatest value after disasters, such as bridge collapses, when careful analysis is needed to establish the cause or causes of the failure.
As with all modern scientific and technological endeavors, computers and software play an increasingly important role. As well as the typical business application software there are a number of computer aided applications (computer-aided technologies) specifically for engineering. Computers can be used to generate models of fundamental physical processes, which can be solved using numerical methods.
One of the most widely used design tools in the profession is computer-aided design (CAD) software like CATIA, Autodesk Inventor, DSS SolidWorks or Pro Engineer which enables engineers to create 3D models, 2D drawings, and schematics of their designs. CAD together with digital mockup (DMU) and CAE software such as finite element method analysis or analytic element method allows engineers to create models of designs that can be analyzed without having to make expensive and time-consuming physical prototypes.
These allow products and components to be checked for flaws; assess fit and assembly; study ergonomics; and to analyze static and dynamic characteristics of systems such as stresses, temperatures, electromagnetic emissions, electrical currents and voltages, digital logic levels, fluid flows, and kinematics. Access and distribution of all this information is generally organized with the use of product data management software.
There are also many tools to support specific engineering tasks such as computer-aided manufacturing (CAM) software to generate CNC machining instructions; manufacturing process management software for production engineering; EDA for printed circuit board (PCB) and circuit schematics for electronic engineers; MRO applications for maintenance management; and AEC software for civil engineering.
In recent years the use of computer software to aid the development of goods has collectively come to be known as product life cycle management (PLM).
Click on any of the following hyperlinks for further amplification:
The discipline of engineering is extremely broad, and encompasses a range of more specialized fields of engineering, each with a more specific emphasis on particular areas of applied science, technology and types of application.
Definition:
The American Engineers' Council for Professional Development (ECPD, the predecessor of ABET) has defined "engineering" as:
"The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation or safety to life and property."
History:
Engineering has existed since ancient times as humans devised fundamental inventions such as the wedge, lever, wheel, and pulley. Each of these inventions is essentially consistent with the modern definition of engineering.
The term engineering deriving from the word engineer, which itself dates back to 1300, when an engine'er (literally, one who operates an engine) originally referred to "a constructor of military engines." In this context, now obsolete, an "engine" referred to a military machine, i.e., a mechanical contraption used in war (for example, a catapult).
Notable examples of the obsolete usage which have survived to the present day are military engineering corps, e.g., the U.S. Army Corps of Engineers.
The word "engine" itself is of even older origin, ultimately deriving from the Latin ingenium (c. 1250), meaning "innate quality, especially mental power, hence a clever invention."
Later, as the design of civilian structures such as bridges and buildings matured as a technical discipline, the term civil engineering entered the lexicon as a way to distinguish between those specializing in the construction of such non-military projects and those involved in the older discipline of military engineering.
Disciplines:
Engineering is a broad discipline which is often broken down into several sub-disciplines. These disciplines concern themselves with differing areas of engineering work. Although initially an engineer will usually be trained in a specific discipline, throughout an engineer's career the engineer may become multi-disciplined, having worked in several of the outlined areas. Engineering is often characterized as having four main branches:
- Chemical engineering – The application of physics, chemistry, biology, and engineering principles in order to carry out chemical processes on a commercial scale, such as petroleum refining, micro-fabrication, fermentation, and bio-molecule production.
- Civil engineering – The design and construction of public and private works, such as infrastructure (airports, roads, railways, water supply and treatment etc.), bridges, dams, and buildings.
- Electrical engineering – The design, study and manufacture of various electrical and electronic systems, such as electrical circuits, generators, motors, electromagnetic/electro-mechanical devices, electronic devices,electronic circuits, optical fibers, opto-electronic devices, computer systems, telecommunications, instrumentation, controls, and electronics.
- Mechanical engineering – The design and manufacture of physical or mechanical systems, such as power and energy systems, aerospace/aircraft products, weapon systems, transportation products, engines, compressors, power trains, kinematic chains, vacuum technology, vibration isolation equipment, manufacturing, and mechatronics.
Beyond these four, a number of other branches are recognized. Historically, naval engineering and mining engineering were major branches. Other engineering fields sometimes included as major branches are,
- manufacturing engineering,
- acoustical engineering,
- corrosion engineering,
- Instrumentation and control,
- aerospace,
- automotive,
- computer,
- electronic,
- petroleum,
- systems,
- audio,
- software,
- architectural,
- agricultural,
- biosystems,
- biomedical,
- geological,
- textile,
- industrial,
- materials,
- and nuclear engineering.
New specialties sometimes combine with the traditional fields and form new branches - for example Earth Systems Engineering and Management involves a wide range of subject areas including anthropology, engineering studies, environmental science, ethics and philosophy.
A new or emerging area of application will commonly be defined temporarily as a permutation or subset of existing disciplines; there is often gray area as to when a given sub-field warrants classification as a new "branch." One key indicator of such emergence is when major universities start establishing departments and programs in the new field.
For each of these fields there exists considerable overlap, especially in the areas of the application of fundamental sciences to their disciplines such as physics, chemistry, and mathematics.
Engineers apply mathematics and sciences such as physics to find suitable solutions to problems or to make improvements to the status quo. More than ever, engineers are now required to have knowledge of relevant sciences for their design projects. As a result, they may keep on learning new material throughout their career.
If multiple options exist, engineers weigh different design choices on their merits and choose the solution that best matches the requirements. The crucial and unique task of the engineer is to identify, understand, and interpret the constraints on a design in order to produce a successful result. It is usually not enough to build a technically successful product; it must also meet further requirements.
Constraints may include available resources, physical, imaginative or technical limitations, flexibility for future modifications and additions, and other factors, such as requirements for cost, safety, marketability, productivity, and serviceability. By understanding the constraints, engineers derive specifications for the limits within which a viable object or system may be produced and operated.
A general methodology and epistemology of engineering can be inferred from the historical case studies and comments provided by Walter Vincenti. Though Vincenti's case studies are from the domain of aeronautical engineering, his conclusions can be transferred into many other branches of engineering, too.
According to Billy Vaughn Koen, the "engineering method is the use of heuristics to cause the best change in a poorly understood situation within the available resources." Koen argues that the definition of what makes one an engineer should not be based on what he produces, but rather how he goes about it.
Engineers use their knowledge of science, mathematics, logic, economics, and appropriate experience or tacit knowledge to find suitable solutions to a problem. Creating an appropriate mathematical model of a problem allows them to analyze it (sometimes definitively), and to test potential solutions.
Usually multiple reasonable solutions exist, so engineers must evaluate the different design choices on their merits and choose the solution that best meets their requirements.
Genrich Altshuller, after gathering statistics on a large number of patents, suggested that compromises are at the heart of "low-level" engineering designs, while at a higher level the best design is one which eliminates the core contradiction causing the problem.
Engineers typically attempt to predict how well their designs will perform to their specifications prior to full-scale production. They use, among other things: prototypes, scale models, simulations, destructive tests, nondestructive tests, and stress tests. Testing ensures that products will perform as expected.
Engineers take on the responsibility of producing designs that will perform as well as expected and will not cause unintended harm to the public at large. Engineers typically include a factor of safety in their designs to reduce the risk of unexpected failure. However, the greater the safety factor, the less efficient the design may be.
The study of failed products is known as forensic engineering, and can help the product designer in evaluating his or her design in the light of real conditions. The discipline is of greatest value after disasters, such as bridge collapses, when careful analysis is needed to establish the cause or causes of the failure.
As with all modern scientific and technological endeavors, computers and software play an increasingly important role. As well as the typical business application software there are a number of computer aided applications (computer-aided technologies) specifically for engineering. Computers can be used to generate models of fundamental physical processes, which can be solved using numerical methods.
One of the most widely used design tools in the profession is computer-aided design (CAD) software like CATIA, Autodesk Inventor, DSS SolidWorks or Pro Engineer which enables engineers to create 3D models, 2D drawings, and schematics of their designs. CAD together with digital mockup (DMU) and CAE software such as finite element method analysis or analytic element method allows engineers to create models of designs that can be analyzed without having to make expensive and time-consuming physical prototypes.
These allow products and components to be checked for flaws; assess fit and assembly; study ergonomics; and to analyze static and dynamic characteristics of systems such as stresses, temperatures, electromagnetic emissions, electrical currents and voltages, digital logic levels, fluid flows, and kinematics. Access and distribution of all this information is generally organized with the use of product data management software.
There are also many tools to support specific engineering tasks such as computer-aided manufacturing (CAM) software to generate CNC machining instructions; manufacturing process management software for production engineering; EDA for printed circuit board (PCB) and circuit schematics for electronic engineers; MRO applications for maintenance management; and AEC software for civil engineering.
In recent years the use of computer software to aid the development of goods has collectively come to be known as product life cycle management (PLM).
Click on any of the following hyperlinks for further amplification:
- Social context
- Relationships with other disciplines
- See also:
- Main article: Outline of engineering
Lists - List of engineering topics
- List of engineers
- Engineering society
- List of aerospace engineering topics
- List of basic chemical engineering topics
- List of electrical engineering topics
- List of Engineering Branches
- List of genetic engineering topics
- List of mechanical engineering topics
- List of nanoengineering topics
- List of software engineering topics
- Main article: Outline of engineering
- Glossaries:
- Related subjects:
- Controversies over the term Engineer
- Design
- Earthquake engineering
- Engineer
- Engineering economics
- Engineering education
- Engineering education research
- Engineers Without Borders
- Forensic engineering
- Global Engineering Education
- Industrial design
- Infrastructure
- Mathematics
- Open hardware
- Reverse engineering
- Science
- Science and technology
- Structural failure
- Sustainable engineering
- Women in engineering
- Planned obsolescence
Formal Science
YouTube Video: What is Formal Science?
Pictured: the Structure of Formal Science and its Studies
Formal sciences are disciplines concerned with formal systems, such as:
Whereas the natural sciences seek to characterize physical systems, the formal sciences are concerned with characterizing abstract structures described by sign systems. The formal sciences aid the natural sciences by providing information about the structures the latter use to describe the world, and what inferences may be made about them.
Differences from other forms of science:
"One reason why mathematics enjoys special esteem, above all other sciences, is that its laws are absolutely certain and indisputable, while those of other sciences are to some extent debatable and in constant danger of being overthrown by newly discovered facts."
— Albert Einstein
As opposed to empirical sciences (natural and social), the formal sciences do not involve empirical procedures. They also do not presuppose knowledge of contingent facts, or describe the real world. In this sense, formal sciences are both logically and methodologically a priori, for their content and validity are independent of any empirical procedures.
Although formal sciences are conceptual systems, lacking empirical content, this does not mean that they have no relation to the real world. But this relation is such that their formal statements hold in all possible conceivable worlds (see valid formula) – whereas, statements based on empirical theories, such as, say, general relativity or evolutionary biology, do not hold in all possible worlds, and may eventually turn out not to hold in this world as well.
That is why formal sciences are applicable in all domains and useful in all empirical sciences.
Because of their non-empirical nature, formal sciences are construed by outlining a set of axioms and definitions from which other statements (theorems) are deduced. In other words, theories in formal sciences contain no synthetic statements; all their statements are analytic.
See Also:
- logic,
- mathematics,
- statistics,
- theoretical computer science,
- information theory,
- game theory,
- systems theory,
- decision theory,
- and portions of linguistics and economics.
Whereas the natural sciences seek to characterize physical systems, the formal sciences are concerned with characterizing abstract structures described by sign systems. The formal sciences aid the natural sciences by providing information about the structures the latter use to describe the world, and what inferences may be made about them.
Differences from other forms of science:
"One reason why mathematics enjoys special esteem, above all other sciences, is that its laws are absolutely certain and indisputable, while those of other sciences are to some extent debatable and in constant danger of being overthrown by newly discovered facts."
— Albert Einstein
As opposed to empirical sciences (natural and social), the formal sciences do not involve empirical procedures. They also do not presuppose knowledge of contingent facts, or describe the real world. In this sense, formal sciences are both logically and methodologically a priori, for their content and validity are independent of any empirical procedures.
Although formal sciences are conceptual systems, lacking empirical content, this does not mean that they have no relation to the real world. But this relation is such that their formal statements hold in all possible conceivable worlds (see valid formula) – whereas, statements based on empirical theories, such as, say, general relativity or evolutionary biology, do not hold in all possible worlds, and may eventually turn out not to hold in this world as well.
That is why formal sciences are applicable in all domains and useful in all empirical sciences.
Because of their non-empirical nature, formal sciences are construed by outlining a set of axioms and definitions from which other statements (theorems) are deduced. In other words, theories in formal sciences contain no synthetic statements; all their statements are analytic.
See Also:
- Rationalism
- Abstract structure
- Abstraction in mathematics
- Abstraction in computer science
- Formal grammar
- Formal language
- Formal method
- Formal system
- Mathematical model
Genetics including Genetic Testing
YouTube Video: What is Genetic Engineering?
YouTube Video: Benefits and Limitations of Genetic Testing
Pictured: FAQs about Genetic Testing (NIH)
Genetics is the study of genes, genetic variation, and heredity in living organisms. It is generally considered a field of biology, but it intersects frequently with many of the life sciences and is strongly linked with the study of information systems.
The father of genetics is Gregor Mendel, a late 19th-century scientist and Augustinian friar. Mendel studied 'trait inheritance', patterns in the way traits were handed down from parents to offspring. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene.
Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded beyond inheritance to studying the function and behavior of genes.
Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance) and within the context of a population. Genetics has given rise to a number of sub-fields including epigenetics and population genetics.
Organisms studied within the broad field span the domain of life, including bacteria, plants, animals, and humans.
Genetic processes work in combination with an organism's environment and experiences to influence development and behavior, often referred to as nature versus nurture. The intra- or extra-cellular environment of a cell or organism may switch gene transcription on or off. A classic example is two seeds of genetically identical corn, one placed in a temperate climate and one in an arid climate.
While the average height of the two corn stalks may be genetically determined to be equal, the one in the arid climate only grows to half the height of the one in the temperate climate due to lack of water and nutrients in its environment.
For amplification, click on any of the following:
Genetic testing, also known as DNA testing, allows the determination of bloodlines and the genetic diagnosis of vulnerabilities to inherited diseases.
In agriculture, a form of genetic testing known as progeny testing can be used to evaluate the quality of breeding stock.
In population ecology, genetic testing can be used to track genetic strengths and vulnerabilities of species populations.
In humans, genetic testing can be used to determine a child's parentage (genetic mother and father) or in general a person's ancestry or biological relationship between people. In addition to studying chromosomes to the level of individual genes, genetic testing in a broader sense includes biochemical tests for the possible presence of genetic diseases, or mutant forms of genes associated with increased risk of developing genetic disorders.
Genetic testing identifies changes in chromosomes, genes, or proteins. The variety of genetic tests has expanded throughout the years. In the past, the main genetic tests searched for abnormal chromosome numbers and mutations that lead to rare, inherited disorders.
Today, tests involve analyzing multiple genes to determine the risk of developing specific diseases or disorders, with the more common diseases consisting of heart disease and cancer.
The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person's chance of developing or passing on a genetic disorder. Several hundred genetic tests are currently in use, and more are being developed.
Because genetic mutations can directly affect the structure of the proteins they code for, testing for specific genetic diseases can also be accomplished by looking at those proteins or their metabolites, or looking at stained or fluorescent chromosomes under a microscope.
Click on any of the following blue hyperlinks for more about Genetic Testing:
The father of genetics is Gregor Mendel, a late 19th-century scientist and Augustinian friar. Mendel studied 'trait inheritance', patterns in the way traits were handed down from parents to offspring. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene.
Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded beyond inheritance to studying the function and behavior of genes.
Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance) and within the context of a population. Genetics has given rise to a number of sub-fields including epigenetics and population genetics.
Organisms studied within the broad field span the domain of life, including bacteria, plants, animals, and humans.
Genetic processes work in combination with an organism's environment and experiences to influence development and behavior, often referred to as nature versus nurture. The intra- or extra-cellular environment of a cell or organism may switch gene transcription on or off. A classic example is two seeds of genetically identical corn, one placed in a temperate climate and one in an arid climate.
While the average height of the two corn stalks may be genetically determined to be equal, the one in the arid climate only grows to half the height of the one in the temperate climate due to lack of water and nutrients in its environment.
For amplification, click on any of the following:
- The gene
- History
- Features of inheritance
- Molecular basis for inheritance
- Gene expression
- Genetic change
- Society and culture
- See also:
Genetic testing, also known as DNA testing, allows the determination of bloodlines and the genetic diagnosis of vulnerabilities to inherited diseases.
In agriculture, a form of genetic testing known as progeny testing can be used to evaluate the quality of breeding stock.
In population ecology, genetic testing can be used to track genetic strengths and vulnerabilities of species populations.
In humans, genetic testing can be used to determine a child's parentage (genetic mother and father) or in general a person's ancestry or biological relationship between people. In addition to studying chromosomes to the level of individual genes, genetic testing in a broader sense includes biochemical tests for the possible presence of genetic diseases, or mutant forms of genes associated with increased risk of developing genetic disorders.
Genetic testing identifies changes in chromosomes, genes, or proteins. The variety of genetic tests has expanded throughout the years. In the past, the main genetic tests searched for abnormal chromosome numbers and mutations that lead to rare, inherited disorders.
Today, tests involve analyzing multiple genes to determine the risk of developing specific diseases or disorders, with the more common diseases consisting of heart disease and cancer.
The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person's chance of developing or passing on a genetic disorder. Several hundred genetic tests are currently in use, and more are being developed.
Because genetic mutations can directly affect the structure of the proteins they code for, testing for specific genetic diseases can also be accomplished by looking at those proteins or their metabolites, or looking at stained or fluorescent chromosomes under a microscope.
Click on any of the following blue hyperlinks for more about Genetic Testing:
- Types
- Medical procedure
- Risks and limitations
- Direct-to-consumer genetic testing
- Government regulation in the United States
- In popular culture
- Ethics
- Costs
- See also:
Geology
YouTube Video "Energy Technologies and Man-made Earthquakes" (The National Academies of Sciences, Engineering, and Medicine)
Pictured: The Earth's layered structure. (1) inner core; (2) outer core; (3) lower mantle; (4) upper mantle; (5) lithosphere; (6) crust (part of the lithosphere) (picture courtesy of “Original Mats Halldin Vectorization: Chabacano, CC BY-SA 3.0)
Geology is an earth science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change.
Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).
Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.
Click on any of the following blue hyperlinks for amplification:
Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).
Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.
Click on any of the following blue hyperlinks for amplification:
- Geologic materials
- Whole-Earth structure
- Geologic time
- Planetary geology
- Applied geology
- Engineering geology
- Hydrology and environmental issues
- Natural hazards
- History of geology
- Fields or related disciplines
- Regional geology
- See also:
Forensic Science
YouTube Video about Forensic Science
Forensic science is the application of science to criminal and civil laws. Forensic scientists collect, preserve, and analyze scientific evidence during the course of an investigation.
While some forensic scientists travel to the scene to collect the evidence themselves, others occupy a laboratory role, performing analysis on objects brought to them by other individuals.
In addition to their laboratory role, forensic scientists testify as expert witnesses in both criminal and civil cases and can work for either the prosecution or the defense. While any field could technically be forensic, certain sections have developed over time to encompass the majority of forensically related cases.
For amplification, click on any of the following hyperlinks:
While some forensic scientists travel to the scene to collect the evidence themselves, others occupy a laboratory role, performing analysis on objects brought to them by other individuals.
In addition to their laboratory role, forensic scientists testify as expert witnesses in both criminal and civil cases and can work for either the prosecution or the defense. While any field could technically be forensic, certain sections have developed over time to encompass the majority of forensically related cases.
For amplification, click on any of the following hyperlinks:
- History
- Subdivisions
- Questionable techniques
- Litigation science
- International demographics
- Examples in popular culture
- Controversies
- Forensic science and humanitarian work
- See also:
- American Academy of Forensic Sciences
- Association of Firearm and Tool Mark Examiners
- Ballistic fingerprinting
- Bloodstain pattern analysis
- Computer forensics
- Crime
- Computational forensics
- Diplomatics (Forensic paleography)
- Fingerprint
- Footprints
- Forensic accounting
- Forensic animation
- Forensic anthropology
- Forensic biology
- Forensic chemistry
- Forensic economics
- Forensic engineering
- Forensic entomology
- Forensic facial reconstruction
- Forensic identification
- Forensic linguistics
- Forensic materials engineering
- Forensic photography
- Forensic polymer engineering
- Forensic profiling
- Forensic psychiatry
- Forensic psychology
- Forensic seismology
- Forensic social work
- Forensic video analysis
- Glove prints
- Marine forensics
- Offender profiling
- Questioned document examination
- Retrospective diagnosis
- RSID
- Scenes of Crime Officer
- Skid mark
- Trace evidence
- Profiling (information science)
- Wildlife Forensic Science
History of Science including Timeline of Scientific Discoveries
YouTube Video about the Top Ten Inventions of All Time according to WatchMojo.com
Pictured: Earthrise over the Moon, Apollo 8, NASA. This image helped create awareness of the finiteness of Earth, and the limits of its natural resources.
The history of science is the study of the development of science and scientific knowledge, including both the natural sciences and social sciences. (The history of the arts and humanities is termed as the history of scholarship.)
Science is a body of empirical, theoretical, and practical knowledge about the natural world, produced by scientists who emphasize the observation, explanation, and prediction of real world phenomena.
Historiography of science, in contrast, often draws on the historical methods of both intellectual history and social history.
The English word scientist is relatively recent—first coined by William Whewell in the 19th century. Previously, people investigating nature called themselves natural philosophers. While empirical investigations of the natural world have been described since classical antiquity (for example, by Thales, Aristotle, and others), and scientific methods have been employed since the Middle Ages (for example, by Ibn al-Haytham, and Roger Bacon), the dawn of modern science is often traced back to the early modern period and in particular to the scientific revolution that took place in 16th- and 17th-century Europe.
Scientific methods are considered to be so fundamental to modern science that some consider earlier inquiries into nature to be pre-scientific. Traditionally, historians of science have defined science sufficiently broadly to include those inquiries.
From the 18th century through late 20th century, the history of science, especially of the physical and biological sciences, was often presented in a progressive narrative in which true theories replaced false beliefs.
Some more recent historical interpretations, such as those of Thomas Kuhn, tend to portray the history of science in different terms, such as that of competing paradigms or conceptual systems in a wider matrix that includes intellectual, cultural, economic and political themes outside of science.
For amplification, click on any of the following blue hyperlinks:
Science is a body of empirical, theoretical, and practical knowledge about the natural world, produced by scientists who emphasize the observation, explanation, and prediction of real world phenomena.
Historiography of science, in contrast, often draws on the historical methods of both intellectual history and social history.
The English word scientist is relatively recent—first coined by William Whewell in the 19th century. Previously, people investigating nature called themselves natural philosophers. While empirical investigations of the natural world have been described since classical antiquity (for example, by Thales, Aristotle, and others), and scientific methods have been employed since the Middle Ages (for example, by Ibn al-Haytham, and Roger Bacon), the dawn of modern science is often traced back to the early modern period and in particular to the scientific revolution that took place in 16th- and 17th-century Europe.
Scientific methods are considered to be so fundamental to modern science that some consider earlier inquiries into nature to be pre-scientific. Traditionally, historians of science have defined science sufficiently broadly to include those inquiries.
From the 18th century through late 20th century, the history of science, especially of the physical and biological sciences, was often presented in a progressive narrative in which true theories replaced false beliefs.
Some more recent historical interpretations, such as those of Thomas Kuhn, tend to portray the history of science in different terms, such as that of competing paradigms or conceptual systems in a wider matrix that includes intellectual, cultural, economic and political themes outside of science.
For amplification, click on any of the following blue hyperlinks:
- Early cultures
- Science in the Middle Ages
- Impact of science in Europe
- Modern science
- Academic study
- See also (other topics)
Mathematics and Fields of Mathematics
Humorous YouTube Video from the TV show "The Big Bang Theory" about Sheldon using mathematics to engage in social discourse.
Pictured: The mathematical sciences and their interfaces. SOURCE: Adapted from National Science Foundation, 1998, Report of the Senior Assessment Panel for the International Assessment of the U.S. Mathematical Sciences, NSF, Arlington, Va.
There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics.
Mathematicians seek out patterns and use them to formulate new conjectures.
Mathematicians resolve the truth or falsity of conjectures by mathematical proof. When mathematical structures are good models of real phenomena, then mathematical reasoning can provide insight or predictions about nature.
Through the use of abstraction and logic, mathematics developed from counting, calculation, measurement, and the systematic study of the shapes and motions of physical objects.
Practical mathematics has been a human activity for as far back as written records exist. The research required to solve mathematical problems can take years or even centuries of sustained inquiry. Rigorous arguments first appeared in Greek mathematics, most notably in Euclid's Elements.
Since the pioneering work of Giuseppe Peano (1858–1932), David Hilbert (1862–1943), and others on axiomatic systems in the late 19th century, it has become customary to view mathematical research as establishing truth by rigorous deduction from appropriately chosen axioms and definitions. Mathematics developed at a relatively slow pace until the Renaissance, when mathematical innovations interacting with new scientific discoveries led to a rapid increase in the rate of mathematical discovery that has continued to the present day.
Galileo Galilei (1564–1642) said, "The universe cannot be read until we have learned the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word. Without these, one is wandering about in a dark labyrinth."
Carl Friedrich Gauss (1777–1855) referred to mathematics as "the Queen of the Sciences". Benjamin Peirce (1809–1880) called mathematics "the science that draws necessary conclusions".
David Hilbert said of mathematics: "We are not speaking here of arbitrariness in any sense. Mathematics is not like a game whose tasks are determined by arbitrarily stipulated rules. Rather, it is a conceptual system possessing internal necessity that can only be so and by no means otherwise." Albert Einstein (1879–1955) stated that "as far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality."
Mathematics is essential in many fields, including,
Applied mathematics has led to entirely new mathematical disciplines, such as statistics and game theory. Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind. There is no clear line separating pure and applied mathematics, and practical applications for what began as pure mathematics are often discovered.
For additional information about the Fields of Mathematics, click here.
Mathematicians seek out patterns and use them to formulate new conjectures.
Mathematicians resolve the truth or falsity of conjectures by mathematical proof. When mathematical structures are good models of real phenomena, then mathematical reasoning can provide insight or predictions about nature.
Through the use of abstraction and logic, mathematics developed from counting, calculation, measurement, and the systematic study of the shapes and motions of physical objects.
Practical mathematics has been a human activity for as far back as written records exist. The research required to solve mathematical problems can take years or even centuries of sustained inquiry. Rigorous arguments first appeared in Greek mathematics, most notably in Euclid's Elements.
Since the pioneering work of Giuseppe Peano (1858–1932), David Hilbert (1862–1943), and others on axiomatic systems in the late 19th century, it has become customary to view mathematical research as establishing truth by rigorous deduction from appropriately chosen axioms and definitions. Mathematics developed at a relatively slow pace until the Renaissance, when mathematical innovations interacting with new scientific discoveries led to a rapid increase in the rate of mathematical discovery that has continued to the present day.
Galileo Galilei (1564–1642) said, "The universe cannot be read until we have learned the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word. Without these, one is wandering about in a dark labyrinth."
Carl Friedrich Gauss (1777–1855) referred to mathematics as "the Queen of the Sciences". Benjamin Peirce (1809–1880) called mathematics "the science that draws necessary conclusions".
David Hilbert said of mathematics: "We are not speaking here of arbitrariness in any sense. Mathematics is not like a game whose tasks are determined by arbitrarily stipulated rules. Rather, it is a conceptual system possessing internal necessity that can only be so and by no means otherwise." Albert Einstein (1879–1955) stated that "as far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality."
Mathematics is essential in many fields, including,
- natural science,
- engineering,
- medicine,
- finance,
- and the social sciences.
Applied mathematics has led to entirely new mathematical disciplines, such as statistics and game theory. Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind. There is no clear line separating pure and applied mathematics, and practical applications for what began as pure mathematics are often discovered.
For additional information about the Fields of Mathematics, click here.
Medicine, Medical Specialties and Timeline of Medicine and Medical Technology
YouTube: Robotic Surgery Demonstration Using Da Vinci Surgical System
Pictured: LEFT: Louis Pasteur in his laboratory, 1885; RIGHT: Image of a typical positron emission tomography (PET) facility
Click here for a List of Medical Specialties.
Click here for a Timeline of Medical Technology
Medicine is the science and practice of the diagnosis, treatment, and prevention of disease.
Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness. Contemporary medicine applies biomedical sciences, biomedical research, genetics, and medical technology to diagnose, treat, and prevent injury and disease, typically through pharmaceuticals or surgery, but also through therapies as diverse as psychotherapy, external splints and traction, medical devices, biologics, and ionizing radiation, among others.
Medicine has existed for thousands of years, during most of which it was an art (an area of skill and knowledge) frequently having connections to the religious and philosophical beliefs of local culture.
For example, a medicine man would apply herbs and say prayers for healing, or an ancient philosopher and physician would apply bloodletting according to the theories of humorism.
In recent centuries, since the advent of modern science, most medicine has become a combination of art and science (both basic and applied, under the umbrella of medical science).
While stitching technique for sutures is an art learned through practice, the knowledge of what happens at the cellular and molecular level in the tissues being stitched arises through science.
Pre-scientific forms of medicine are now known as traditional medicine and folk medicine. They remain commonly used with or instead of scientific medicine and are thus called alternative medicine. For example, evidence on the effectiveness of acupuncture is "variable and inconsistent" for any condition, but is generally safe when done by an appropriately trained practitioner.
In contrast, treatments outside the bounds of safety and efficacy are termed quackery.
For the Fields of Medicine and other amplification, click on any of the following:
Click here for a Timeline of Medical Technology
Medicine is the science and practice of the diagnosis, treatment, and prevention of disease.
Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness. Contemporary medicine applies biomedical sciences, biomedical research, genetics, and medical technology to diagnose, treat, and prevent injury and disease, typically through pharmaceuticals or surgery, but also through therapies as diverse as psychotherapy, external splints and traction, medical devices, biologics, and ionizing radiation, among others.
Medicine has existed for thousands of years, during most of which it was an art (an area of skill and knowledge) frequently having connections to the religious and philosophical beliefs of local culture.
For example, a medicine man would apply herbs and say prayers for healing, or an ancient philosopher and physician would apply bloodletting according to the theories of humorism.
In recent centuries, since the advent of modern science, most medicine has become a combination of art and science (both basic and applied, under the umbrella of medical science).
While stitching technique for sutures is an art learned through practice, the knowledge of what happens at the cellular and molecular level in the tissues being stitched arises through science.
Pre-scientific forms of medicine are now known as traditional medicine and folk medicine. They remain commonly used with or instead of scientific medicine and are thus called alternative medicine. For example, evidence on the effectiveness of acupuncture is "variable and inconsistent" for any condition, but is generally safe when done by an appropriately trained practitioner.
In contrast, treatments outside the bounds of safety and efficacy are termed quackery.
For the Fields of Medicine and other amplification, click on any of the following:
- Clinical practice
- Institutions
- Branches
- Education and legal controls
- Medical ethics
- History
- Traditional medicine
- See also:
- Main articles: Outline of medicine and Outline of health
- List of causes of death by rate
- List of disorders
- List of important publications in medicine
- Lists of diseases
- Medical encyclopedia
- Medical equipment
- Medical coding
- Medical billing
- Medical literature
- Medical psychology
- Medical sociology
- Philosophy of healthcare
Natural Sciences
YouTube Video: Hawaii's Kilauea volcano eruption forces evacuations
Pictured: The natural sciences seek to understand how the world and universe around us works. There are five major branches (top left to bottom right): Chemistry, astronomy, earth science, physics, and biology.
Natural science is a branch of science concerned with the description, prediction, and understanding of natural phenomena, based on observational and empirical evidence. Mechanisms such as peer review and repetitiveness of findings are used to try to ensure the validity of scientific advances.
Natural science can be divided into two main branches:
These branches of natural science may be further divided into more specialized branches (also known as fields).
In Western society's analytic tradition, the empirical sciences and especially natural sciences use tools from formal sciences, such as mathematics and logic, converting information about nature into measurements which can be explained as clear statements of the "laws of nature".
The social sciences also use such methods, but rely more on qualitative research, so that they are sometimes called "soft science", whereas natural sciences, insofar as they emphasize quantifiable data produced, tested, and confirmed through the scientific method, are sometimes called "hard science".
Modern natural science succeeded more classical approaches to natural philosophy, usually traced to ancient Greece. Galileo, Descartes, Francis Bacon, and Newton debated the benefits of using approaches which were more mathematical and more experimental in a methodical way.
Still, philosophical perspectives, conjectures, and presuppositions, often overlooked, remain requisite in natural science. Systematic data collection, including discovery science, succeeded natural history, which emerged in the 16th century by describing and classifying plants, animals, minerals, and so on.
Today, "natural history" suggests observational descriptions aimed at popular audiences.
For amplification, click on any of the following:
Natural science can be divided into two main branches:
- life science (or biological science);
- and physical science. Physical science can be further subdivided into branches:
- physics,
- astronomy,
- chemistry,
- and Earth science.
These branches of natural science may be further divided into more specialized branches (also known as fields).
In Western society's analytic tradition, the empirical sciences and especially natural sciences use tools from formal sciences, such as mathematics and logic, converting information about nature into measurements which can be explained as clear statements of the "laws of nature".
The social sciences also use such methods, but rely more on qualitative research, so that they are sometimes called "soft science", whereas natural sciences, insofar as they emphasize quantifiable data produced, tested, and confirmed through the scientific method, are sometimes called "hard science".
Modern natural science succeeded more classical approaches to natural philosophy, usually traced to ancient Greece. Galileo, Descartes, Francis Bacon, and Newton debated the benefits of using approaches which were more mathematical and more experimental in a methodical way.
Still, philosophical perspectives, conjectures, and presuppositions, often overlooked, remain requisite in natural science. Systematic data collection, including discovery science, succeeded natural history, which emerged in the 16th century by describing and classifying plants, animals, minerals, and so on.
Today, "natural history" suggests observational descriptions aimed at popular audiences.
For amplification, click on any of the following:
- Criteria
- Branches of natural science
- Interdisciplinary studies
- History
- See also:
- Empiricism
- Branches of science
- List of academic disciplines and sub-disciplines
- Natural Sciences (Cambridge), for the Tripos at the University of Cambridge
Physics
YouTube Video from the TV Show "The Big Bang Theory" - Sheldon teaches Penny Physics
Pictured: Various examples of physical phenomena.
Physics is the natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force.
One of the most fundamental scientific disciplines, the main goal of physics is to understand how the universe behaves.
Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy.
Over the last two millennia, physics was a part of natural philosophy along with chemistry, biology, and certain branches of mathematics. However, during the scientific revolution in the 17th century, the natural sciences emerged as unique research programs in their own right.
Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined.
New ideas in physics often explain the fundamental mechanisms of other sciences while opening new avenues of research in areas such as mathematics and philosophy.
Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs.
For example, advances in the understanding of electromagnetism or nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons. Advances in thermodynamics led to the development of industrialization, and advances in mechanics inspired the development of calculus.
For Amplification, click on any of the Hyperlinks below:
One of the most fundamental scientific disciplines, the main goal of physics is to understand how the universe behaves.
Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy.
Over the last two millennia, physics was a part of natural philosophy along with chemistry, biology, and certain branches of mathematics. However, during the scientific revolution in the 17th century, the natural sciences emerged as unique research programs in their own right.
Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined.
New ideas in physics often explain the fundamental mechanisms of other sciences while opening new avenues of research in areas such as mathematics and philosophy.
Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs.
For example, advances in the understanding of electromagnetism or nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons. Advances in thermodynamics led to the development of industrialization, and advances in mechanics inspired the development of calculus.
For Amplification, click on any of the Hyperlinks below:
- History
- Philosophy
- Core theories
- Relation to other fields
- Research
- Current research
- See also:
- Glossary of classical physics
- Glossary of physics
- Index of physics articles
- List of elementary physics formulae, Elementary physics formulae
- List of important publications in physics
- List of physicists
- List of physics concepts in primary and secondary education curricula
- Outline of physics
- Physics outreach
- Perfection in physics and chemistry
- Relationship between mathematics and physics
- Timeline of developments in theoretical physics
- Timeline of fundamental physics discoveries
Science Centers
YouTube Video of the Omnimax Theater Presentation at the St. Louis Science Center: Robots
Pictured: A display inside the St. Louis Science Center
Science centers or science centers are science museums that emphasize a hands-on approach, featuring interactive exhibits that encourage visitors to experiment and explore.
The first science center was Urania founded in Berlin in 1888.
The Academy of Science of Saint Louis (founded in 1856) created the Saint Louis Museum of Science and Natural History in 1959 (Saint Louis Science Center), but generally science centers are a product of the 1960s and later.
The first "science center" in the United States was the Science Center of Pinellas County, founded in 1959. The Pacific Science Center (one of the first large organizations to call itself a "science center" rather than a museum) opened in a Seattle World's Fair building in 1962.
The Smithsonian Institution invited visitors into a new Discovery Room in its National Museum of Natural History in Washington, DC, where they could touch and handle formerly off-limits specimens.
In 1969, Oppenheimer's Exploratorium opened in San Francisco, California, and the Ontario Science Center opened near Toronto, Canada.
By the early 1970s, COSI Columbus, then known as the Center of Science and Industry in Columbus, Ohio, had run its first "camp-in."
It did not take long for these new-style museums to band together for mutual support. In 1971, 16 museum directors gathered to discuss the possibility of starting a new association — one more specifically tailored to their needs than the existing American Association of Museums (now the American Alliance of Museums).
The Association of Science-Technology Centers (ASTC) was formally established in 1973, headquartered in Washington DC, but with an international organizational membership. The corresponding European organization is ECSITE.
See also:
The first science center was Urania founded in Berlin in 1888.
The Academy of Science of Saint Louis (founded in 1856) created the Saint Louis Museum of Science and Natural History in 1959 (Saint Louis Science Center), but generally science centers are a product of the 1960s and later.
The first "science center" in the United States was the Science Center of Pinellas County, founded in 1959. The Pacific Science Center (one of the first large organizations to call itself a "science center" rather than a museum) opened in a Seattle World's Fair building in 1962.
The Smithsonian Institution invited visitors into a new Discovery Room in its National Museum of Natural History in Washington, DC, where they could touch and handle formerly off-limits specimens.
In 1969, Oppenheimer's Exploratorium opened in San Francisco, California, and the Ontario Science Center opened near Toronto, Canada.
By the early 1970s, COSI Columbus, then known as the Center of Science and Industry in Columbus, Ohio, had run its first "camp-in."
It did not take long for these new-style museums to band together for mutual support. In 1971, 16 museum directors gathered to discuss the possibility of starting a new association — one more specifically tailored to their needs than the existing American Association of Museums (now the American Alliance of Museums).
The Association of Science-Technology Centers (ASTC) was formally established in 1973, headquartered in Washington DC, but with an international organizational membership. The corresponding European organization is ECSITE.
See also:
- Science museum
- List of science museums
- Science festival
- University City Science Center, Philadelphia, PA
- Science exhibits
The Smithsonian Institution
YouTube Video: About the Smithsonian Institution
Pictured: The "Castle" (1847), the Institution's first building and still its headquarters
The Smithsonian Institution, established in 1846 "for the increase and diffusion of knowledge," is a group of museums and research centers administered by the Government of the United States.
Originally organized as the "United States National Museum," that name ceased to exist as an administrative entity in 1967.
Termed "the nation's attic" for its eclectic holdings of 138 million items, the Institution's nineteen museums, nine research centers, and zoo include historical and architectural landmarks, mostly located in the District of Columbia.
Additional facilities are located in Arizona, Maryland, Massachusetts, New York City, Virginia, and Panama.
A further 170 museums are Smithsonian Affiliates. The Institution's thirty million annual visitors are admitted without charge. Funding comes from the Institution's endowment, private and corporate contributions, membership dues, government support, as well as retail, concession and licensing revenues.
Institution publications include Smithsonian and Air & Space magazines.
Click here for further amplification.
Originally organized as the "United States National Museum," that name ceased to exist as an administrative entity in 1967.
Termed "the nation's attic" for its eclectic holdings of 138 million items, the Institution's nineteen museums, nine research centers, and zoo include historical and architectural landmarks, mostly located in the District of Columbia.
Additional facilities are located in Arizona, Maryland, Massachusetts, New York City, Virginia, and Panama.
A further 170 museums are Smithsonian Affiliates. The Institution's thirty million annual visitors are admitted without charge. Funding comes from the Institution's endowment, private and corporate contributions, membership dues, government support, as well as retail, concession and licensing revenues.
Institution publications include Smithsonian and Air & Space magazines.
Click here for further amplification.
Scientists and Scientific Discoveries by the U.S.
YouTube Video: Remote Control Sports Car | Outrageous Acts of Science
A scientist is a person engaging in a systematic activity to acquire knowledge that describes and predicts the natural world. In a more restricted sense, a scientist may refer to an individual who uses the scientific method.
The person may be an expert in one or more areas of science. This article focuses on the more restricted use of the word. Scientists perform research toward a more comprehensive understanding of nature, including physical, mathematical and social realms.
Philosophy is a distinct activity that is not generally considered science. Philosophers aim to provide a comprehensive understanding of intangible aspects of reality and experience that cannot be physically measured. Even so, the modern Sciences evolved from the Natural Philosophies, a term used to describe all those scholarly studies on the Natural world, as opposed to the Metaphysical, Moral, etc., or the other Medieval fields of study (e.g. Professional doctorate).
Scientists are also distinct from engineers, those who design, build, and maintain devices for particular situations; however, no engineer attains that title without significant study of science and the scientific method.
When science is done with a goal toward practical utility, it is called applied science. An applied scientist may not be designing something in particular, but rather is conducting research with the aim of developing new technologies and practical methods.
When science is done with an inclusion of intangible aspects of reality it is called natural philosophy.
The Timeline of United States discoveries encompasses the breakthroughs of human thought and knowledge of new scientific findings, phenomena, places, things, and what was previously unknown to exist. From a historical stand point, the timeline below of United States discoveries dates from the 18th century to the 21st century, which have been achieved by discoverers who are either native-born or naturalized citizens of the United States.
With an emphasis of discoveries in the fields of astronomy, physics, chemistry, medicine, biology, geology, paleontology, and archaeology, United States citizens acclaimed in their professions have contributed much.
For example, the "Bone Wars," beginning in 1877 and ending in 1892, was an intense period of rivalry between two American paleontologists, Edward Drinker Cope and Othniel Charles Marsh, who initiated several expeditions throughout North America in the pursuit of discovering, identifying, and finding new species of dinosaur fossils. In total, their large efforts resulted in when 142 species of dinosaurs being discovered.
With the founding of the National Aeronautics and Space Administration (NASA) in 1958, a vision and continued commitment by the United States of finding extraterrestrial and astronomical discoveries has helped the world to better understand our solar system and universe.
As one example, in 2008, the Phoenix Mars Lander discovered the presence of frozen water on the planet Mars of which scientists such as Peter H. Smith of the University of Arizona Lunar and Planetary Laboratory (LPL) had suspected before the mission confirmed its existence.
Below, click on the following two links for discoveries of the 20th and 21st Centuries:
Click here for further amplification.
The person may be an expert in one or more areas of science. This article focuses on the more restricted use of the word. Scientists perform research toward a more comprehensive understanding of nature, including physical, mathematical and social realms.
Philosophy is a distinct activity that is not generally considered science. Philosophers aim to provide a comprehensive understanding of intangible aspects of reality and experience that cannot be physically measured. Even so, the modern Sciences evolved from the Natural Philosophies, a term used to describe all those scholarly studies on the Natural world, as opposed to the Metaphysical, Moral, etc., or the other Medieval fields of study (e.g. Professional doctorate).
Scientists are also distinct from engineers, those who design, build, and maintain devices for particular situations; however, no engineer attains that title without significant study of science and the scientific method.
When science is done with a goal toward practical utility, it is called applied science. An applied scientist may not be designing something in particular, but rather is conducting research with the aim of developing new technologies and practical methods.
When science is done with an inclusion of intangible aspects of reality it is called natural philosophy.
The Timeline of United States discoveries encompasses the breakthroughs of human thought and knowledge of new scientific findings, phenomena, places, things, and what was previously unknown to exist. From a historical stand point, the timeline below of United States discoveries dates from the 18th century to the 21st century, which have been achieved by discoverers who are either native-born or naturalized citizens of the United States.
With an emphasis of discoveries in the fields of astronomy, physics, chemistry, medicine, biology, geology, paleontology, and archaeology, United States citizens acclaimed in their professions have contributed much.
For example, the "Bone Wars," beginning in 1877 and ending in 1892, was an intense period of rivalry between two American paleontologists, Edward Drinker Cope and Othniel Charles Marsh, who initiated several expeditions throughout North America in the pursuit of discovering, identifying, and finding new species of dinosaur fossils. In total, their large efforts resulted in when 142 species of dinosaurs being discovered.
With the founding of the National Aeronautics and Space Administration (NASA) in 1958, a vision and continued commitment by the United States of finding extraterrestrial and astronomical discoveries has helped the world to better understand our solar system and universe.
As one example, in 2008, the Phoenix Mars Lander discovered the presence of frozen water on the planet Mars of which scientists such as Peter H. Smith of the University of Arizona Lunar and Planetary Laboratory (LPL) had suspected before the mission confirmed its existence.
Below, click on the following two links for discoveries of the 20th and 21st Centuries:
Click here for further amplification.
Technological and Industrial History of the United States
YouTube Video about American Inventions
Pictured: American Inventions
The technological and industrial history of the United States describes the United States' emergence as one of the most technologically advanced nations in the world.
The availability of land and literate labor, the absence of a landed aristocracy, the prestige of entrepreneurship, the diversity of climate and a large easily accessed upscale and literate free market all contributed to America's rapid industrialization.
The availability of capital, development by the free market of navigable rivers, and coastal waterways, and the abundance of natural resources facilitated the cheap extraction of energy all contributed to America's rapid industrialization.
Fast transport by the very large railroad built in the mid-19th century, and the Interstate Highway System built in the late 20th century, enlarged the markets and reducing shipping and production costs.
The legal system facilitated business operations and guaranteed contracts. Cut off from Europe by the embargo and the British blockade in the War of 1812 (1807–15), entrepreneurs opened factories in the Northeast that set the stage for rapid industrialization modeled on British innovations.
From its emergence as an independent nation, the United States has encouraged science and innovation. As a result, the United States has been the birthplace of 161 of Britannica's 321 Greatest Inventions, including items such as,
The early technological and industrial development in the United States was facilitated by a unique confluence of geographical, social, and economic factors.
The relative lack of workers kept United States wages nearly always higher than corresponding British and European workers and provided an incentive to mechanize some tasks.
The United States population had some semi-unique advantages in that they were former British subjects, had high English literacy skills, for that period (over 80% in New England), had strong British institutions, with some minor American modifications, of courts, laws, right to vote, protection of property rights and in many cases personal contacts among the British innovators of the Industrial Revolution.
Americans had a good basic structure to build on. Another major advantage, which the British lacked, was no inherited aristocratic institutions.
The eastern seaboard of the United States, with a great number of rivers and streams along the Atlantic seaboard, provided many potential sites for constructing textile mills necessary for early industrialization.
The technology and information on how to build a textile industry was largely provided by Samuel Slater (1768–1835) who emigrated to New England in 1789. He had studied and worked in British textile mills for a number of years and immigrated to the United States, despite restrictions against it, to try his luck with U.S. manufacturers who were trying to set up a textile industry.
He was offered a full partnership if he could succeed—he did. A vast supply of natural resources, the technological knowledge on how to build and power the necessary machines along with a labor supply of mobile workers, often unmarried females, all aided early industrialization.
The broad knowledge of the Industrial Revolution and Scientific revolution helped facilitate understanding for the construction and invention of new manufacturing businesses and technologies. A limited government that would allow them to succeed or fail on their own merit helped.
After the close of the American Revolution in 1783, the new government continued the strong property rights established under British rule and established a rule of law necessary to protect those property rights. The idea of issuing patents was incorporated into Article I, Section 8 of the Constitution authorizing Congress "to promote the progress of science and useful arts by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.
The invention of the Cotton Gin by American Eli Whitney made cotton potentially a cheap and readily available resource in the United States for use in the new textile industry.
One of the real impetuses for United States entering the Industrial Revolution was the passage of the Embargo Act of 1807, the War of 1812 (1812–14) and the Napoleonic Wars (1803–15) which cut off supplies of new and cheaper Industrial revolution products from Britain. The lack of access to these goods all provided a strong incentive to learn how to develop the industries and to make their own goods instead of simply buying the goods produced by Britain.
Modern productivity researchers have shown that the period in which the greatest economic and technological progress occurred was between the last half of the 19th century and the first half of the 20th. During this period the nation was transformed from an agricultural economy to the foremost industrial power in the world, with more than a third of the global industrial output. This can be illustrated by the index of total industrial production, which increased from 4.29 in 1790 to 1,975.00 in 1913, an increase of 460 times (base year 1850 – 100).
American colonies gained independence in 1783 just as profound changes in industrial production and coordination were beginning to shift production from artisans to factories.
Growth of the nation's transportation infrastructure with internal improvements and a confluence of technological innovations before the Civil War facilitated an expansion in organization, coordination, and scale of industrial production.
Around the turn of the 20th century, American industry had superseded its European counterparts economically and the nation began to assert its military power. Although the Great Depression challenged its technological momentum, America emerged from it and World War II as one of two global superpowers.
In the second half of the 20th century, as the United States was drawn into competition with the Soviet Union for political, economic, and military primacy, the government invested heavily in scientific research and technological development which spawned advances in spaceflight, computing, and biotechnology.
Science, technology, and industry have not only profoundly shaped America's economic success, but have also contributed to its distinct political institutions, social structure, educational system, and cultural identity. American values of limited government, meritocracy, entrepreneurship, and self-sufficiency are drawn from its legacy of pioneering technical advances.
For amplification of specific technologies by Timeline, click on any of the following hyperlinks:
The availability of land and literate labor, the absence of a landed aristocracy, the prestige of entrepreneurship, the diversity of climate and a large easily accessed upscale and literate free market all contributed to America's rapid industrialization.
The availability of capital, development by the free market of navigable rivers, and coastal waterways, and the abundance of natural resources facilitated the cheap extraction of energy all contributed to America's rapid industrialization.
Fast transport by the very large railroad built in the mid-19th century, and the Interstate Highway System built in the late 20th century, enlarged the markets and reducing shipping and production costs.
The legal system facilitated business operations and guaranteed contracts. Cut off from Europe by the embargo and the British blockade in the War of 1812 (1807–15), entrepreneurs opened factories in the Northeast that set the stage for rapid industrialization modeled on British innovations.
From its emergence as an independent nation, the United States has encouraged science and innovation. As a result, the United States has been the birthplace of 161 of Britannica's 321 Greatest Inventions, including items such as,
- the airplane,
- internet,
- microchip,
- laser,
- cellphone,
- refrigerator,
- email,
- microwave,
- personal computer,
- Liquid-crystal display and light-emitting diode technology,
- air conditioning,
- assembly line,
- supermarket,
- bar code,
- automated teller machine,
- and many more.
The early technological and industrial development in the United States was facilitated by a unique confluence of geographical, social, and economic factors.
The relative lack of workers kept United States wages nearly always higher than corresponding British and European workers and provided an incentive to mechanize some tasks.
The United States population had some semi-unique advantages in that they were former British subjects, had high English literacy skills, for that period (over 80% in New England), had strong British institutions, with some minor American modifications, of courts, laws, right to vote, protection of property rights and in many cases personal contacts among the British innovators of the Industrial Revolution.
Americans had a good basic structure to build on. Another major advantage, which the British lacked, was no inherited aristocratic institutions.
The eastern seaboard of the United States, with a great number of rivers and streams along the Atlantic seaboard, provided many potential sites for constructing textile mills necessary for early industrialization.
The technology and information on how to build a textile industry was largely provided by Samuel Slater (1768–1835) who emigrated to New England in 1789. He had studied and worked in British textile mills for a number of years and immigrated to the United States, despite restrictions against it, to try his luck with U.S. manufacturers who were trying to set up a textile industry.
He was offered a full partnership if he could succeed—he did. A vast supply of natural resources, the technological knowledge on how to build and power the necessary machines along with a labor supply of mobile workers, often unmarried females, all aided early industrialization.
The broad knowledge of the Industrial Revolution and Scientific revolution helped facilitate understanding for the construction and invention of new manufacturing businesses and technologies. A limited government that would allow them to succeed or fail on their own merit helped.
After the close of the American Revolution in 1783, the new government continued the strong property rights established under British rule and established a rule of law necessary to protect those property rights. The idea of issuing patents was incorporated into Article I, Section 8 of the Constitution authorizing Congress "to promote the progress of science and useful arts by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.
The invention of the Cotton Gin by American Eli Whitney made cotton potentially a cheap and readily available resource in the United States for use in the new textile industry.
One of the real impetuses for United States entering the Industrial Revolution was the passage of the Embargo Act of 1807, the War of 1812 (1812–14) and the Napoleonic Wars (1803–15) which cut off supplies of new and cheaper Industrial revolution products from Britain. The lack of access to these goods all provided a strong incentive to learn how to develop the industries and to make their own goods instead of simply buying the goods produced by Britain.
Modern productivity researchers have shown that the period in which the greatest economic and technological progress occurred was between the last half of the 19th century and the first half of the 20th. During this period the nation was transformed from an agricultural economy to the foremost industrial power in the world, with more than a third of the global industrial output. This can be illustrated by the index of total industrial production, which increased from 4.29 in 1790 to 1,975.00 in 1913, an increase of 460 times (base year 1850 – 100).
American colonies gained independence in 1783 just as profound changes in industrial production and coordination were beginning to shift production from artisans to factories.
Growth of the nation's transportation infrastructure with internal improvements and a confluence of technological innovations before the Civil War facilitated an expansion in organization, coordination, and scale of industrial production.
Around the turn of the 20th century, American industry had superseded its European counterparts economically and the nation began to assert its military power. Although the Great Depression challenged its technological momentum, America emerged from it and World War II as one of two global superpowers.
In the second half of the 20th century, as the United States was drawn into competition with the Soviet Union for political, economic, and military primacy, the government invested heavily in scientific research and technological development which spawned advances in spaceflight, computing, and biotechnology.
Science, technology, and industry have not only profoundly shaped America's economic success, but have also contributed to its distinct political institutions, social structure, educational system, and cultural identity. American values of limited government, meritocracy, entrepreneurship, and self-sufficiency are drawn from its legacy of pioneering technical advances.
For amplification of specific technologies by Timeline, click on any of the following hyperlinks:
- Colonial era
- Technological systems and infrastructure
- Effects of industrialization
- Military-industrial-academic complex
- Service industry
- Technology and society
- See also:
- Timeline of United States inventions
- Timeline of United States discoveries
- Timeline of electrical and electronic engineering
- List of African American inventors and scientists
- National Inventors Hall of Fame
- Science and technology in the United States
- United States Patent and Trademark Office
- NASA spinoff
- Yankee ingenuity
- History of medicine in the United States
Social Science
YouTube Video: An Animated Introduction to Social Science
Social science is a major category of academic disciplines, concerned with society and the relationships among individuals within a society. It in turn has many branches, each of which is considered a "social science".
Social sciences often include,
The term is also sometimes used to refer specifically to the field of sociology, the original 'science of society', established in the 19th century.
Positivist social scientists use methods resembling those of the natural sciences as tools for understanding society, and so define science in its stricter modern sense.
Interpretivist social scientists, by contrast, may use social critique or symbolic interpretation rather than constructing empirically falsifiable theories, and thus treat science in its broader sense. In modern academic practice, researchers are often eclectic, using multiple methodologies (for instance, by combining the quantitative and qualitative techniques).
The term social research has also acquired a degree of autonomy as practitioners from various disciplines share in its aims and methods.
For further information, click on any of the following hyperlinks:
Social sciences often include,
- anthropology,
- economics,
- demography,
- human geography,
- political science,
- psychology,
- and sociology ,
- in addition to many other fields.
The term is also sometimes used to refer specifically to the field of sociology, the original 'science of society', established in the 19th century.
Positivist social scientists use methods resembling those of the natural sciences as tools for understanding society, and so define science in its stricter modern sense.
Interpretivist social scientists, by contrast, may use social critique or symbolic interpretation rather than constructing empirically falsifiable theories, and thus treat science in its broader sense. In modern academic practice, researchers are often eclectic, using multiple methodologies (for instance, by combining the quantitative and qualitative techniques).
The term social research has also acquired a degree of autonomy as practitioners from various disciplines share in its aims and methods.
For further information, click on any of the following hyperlinks:
Technology
YouTube Video: The Evolution of Technology
(The video takes you on a journey from 1964 to the present, showing old technologies and their progression until they finally converge into one device, and seamlessly integrate themselves into our lives.)
Technology is the collection of techniques, skills, methods and processes used in the production of goods or services or in the accomplishment of objectives, such as scientific investigation.
Technology can be the knowledge of techniques, processes, etc. or it can be embedded in machines, computers, devices and factories, which can be operated by individuals without detailed knowledge of the workings of such things.
Developments in historic times, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. The steady progress of military technology has brought weapons of ever-increasing destructive power, from clubs to nuclear weapons.
Technology has many effects. It has helped develop more advanced economies (including today's global economy) and has allowed the rise of a leisure class. Many technological processes produce unwanted by-products, known as pollution, and deplete natural resources, to the detriment of Earth's environment.
Various implementations of technology influence the values of a society and new technology often raises new ethical questions. Examples include the rise of the notion of efficiency in terms of human productivity, a term originally applied only to machines, and the challenge of traditional norms.
Philosophical debates have arisen over the use of technology, with disagreements over whether technology improves the human condition or worsens it.
Until recently, it was believed that the development of technology was restricted only to human beings, but 21st century scientific studies indicate that other primates and certain dolphin communities have developed simple tools and passed their knowledge to other generations.
Click on any of the following blue hyperlinks for further amplification:
Technology can be the knowledge of techniques, processes, etc. or it can be embedded in machines, computers, devices and factories, which can be operated by individuals without detailed knowledge of the workings of such things.
Developments in historic times, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. The steady progress of military technology has brought weapons of ever-increasing destructive power, from clubs to nuclear weapons.
Technology has many effects. It has helped develop more advanced economies (including today's global economy) and has allowed the rise of a leisure class. Many technological processes produce unwanted by-products, known as pollution, and deplete natural resources, to the detriment of Earth's environment.
Various implementations of technology influence the values of a society and new technology often raises new ethical questions. Examples include the rise of the notion of efficiency in terms of human productivity, a term originally applied only to machines, and the challenge of traditional norms.
Philosophical debates have arisen over the use of technology, with disagreements over whether technology improves the human condition or worsens it.
Until recently, it was believed that the development of technology was restricted only to human beings, but 21st century scientific studies indicate that other primates and certain dolphin communities have developed simple tools and passed their knowledge to other generations.
Click on any of the following blue hyperlinks for further amplification:
- Definition and usage
- Science, engineering and technology
- History
- Philosophy:
- Technicism
Optimism
Skepticism and critics
Appropriate technology
Optimism and skepticism in the 21st century
Complex technological systems
- Technicism
- Competitiveness
- Other animal species
- Future technology
- Click here for further amplification
The Relationship Between Religion and Science
YouTube Video: Francis Collins - The Language of God: A Scientist Presents Evidence of Belief
Pictured: LEFT: Francis Collins; RIGHT Quote from Albert Einstein.
The relationship between religion and science has been a subject of study since classical antiquity, addressed by philosophers, theologians, scientists, and others.
Perspectives from different geographical regions, cultures and historical epochs are diverse, with some characterizing the relationship as one of conflict, others describing it as one of harmony, and others proposing little interaction.
Science acknowledges reason, empiricism, and evidence, while religions include revelation, faith and sacredness while also acknowledging philosophical and metaphysical explanations with regard to the study of the Universe.
Neither science nor religion are unchanging, timeless, or static because both are complex social and cultural endeavors that have changed through time across languages and cultures. Most scientific and technical innovations prior to the Scientific revolution were achieved by societies organized by religious traditions.
Elements of the scientific method were pioneered by ancient pagan, Islamic, and Christian scholars. Roger Bacon, who is often credited with formalizing the scientific method, was a Franciscan friar. Hinduism has historically embraced reason and empiricism, holding that science brings legitimate, but incomplete knowledge of the world. Confucian thought has held different views of science over time. Most Buddhists today view science as complementary to their beliefs.
Events in Europe such as the Galileo affair, associated with the scientific revolution and the Age of Enlightenment, led scholars such as John William Draper to postulate a conflict thesis, holding that religion and science have been in conflict methodologically, factually and politically throughout history. This thesis is held by some contemporary scientists such as Richard Dawkins, Steven Weinberg and Carl Sagan, and some creationists.
While the conflict thesis remains popular for the public, it has lost favor among most contemporary historians of science.
Many scientists, philosophers, and theologians throughout history, such as Francisco Ayala, Kenneth R. Miller and Francis Collins, have seen compatibility or independence between religion and science.
Biologist Stephen Jay Gould, other scientists, and some contemporary theologians hold that religion and science are non-overlapping magisteria, addressing fundamentally separate forms of knowledge and aspects of life. Some theologians or historians of science, including John Lennox, Thomas Berry, Brian Swimme and Ken Wilber propose an interconnection between science and religion, while others such as Ian Barbour believe there are even parallels.
Public acceptance of scientific facts may be influenced by religion; many in the United States reject the idea of evolution by natural selection, especially regarding human beings. Nevertheless, the American National Academy of Sciences has written that "the evidence for evolution can be fully compatible with religious faith", a view officially endorsed by many religious denominations globally.
For further amplification, click on any of the following hyperlinks:
Perspectives from different geographical regions, cultures and historical epochs are diverse, with some characterizing the relationship as one of conflict, others describing it as one of harmony, and others proposing little interaction.
Science acknowledges reason, empiricism, and evidence, while religions include revelation, faith and sacredness while also acknowledging philosophical and metaphysical explanations with regard to the study of the Universe.
Neither science nor religion are unchanging, timeless, or static because both are complex social and cultural endeavors that have changed through time across languages and cultures. Most scientific and technical innovations prior to the Scientific revolution were achieved by societies organized by religious traditions.
Elements of the scientific method were pioneered by ancient pagan, Islamic, and Christian scholars. Roger Bacon, who is often credited with formalizing the scientific method, was a Franciscan friar. Hinduism has historically embraced reason and empiricism, holding that science brings legitimate, but incomplete knowledge of the world. Confucian thought has held different views of science over time. Most Buddhists today view science as complementary to their beliefs.
Events in Europe such as the Galileo affair, associated with the scientific revolution and the Age of Enlightenment, led scholars such as John William Draper to postulate a conflict thesis, holding that religion and science have been in conflict methodologically, factually and politically throughout history. This thesis is held by some contemporary scientists such as Richard Dawkins, Steven Weinberg and Carl Sagan, and some creationists.
While the conflict thesis remains popular for the public, it has lost favor among most contemporary historians of science.
Many scientists, philosophers, and theologians throughout history, such as Francisco Ayala, Kenneth R. Miller and Francis Collins, have seen compatibility or independence between religion and science.
Biologist Stephen Jay Gould, other scientists, and some contemporary theologians hold that religion and science are non-overlapping magisteria, addressing fundamentally separate forms of knowledge and aspects of life. Some theologians or historians of science, including John Lennox, Thomas Berry, Brian Swimme and Ken Wilber propose an interconnection between science and religion, while others such as Ian Barbour believe there are even parallels.
Public acceptance of scientific facts may be influenced by religion; many in the United States reject the idea of evolution by natural selection, especially regarding human beings. Nevertheless, the American National Academy of Sciences has written that "the evidence for evolution can be fully compatible with religious faith", a view officially endorsed by many religious denominations globally.
For further amplification, click on any of the following hyperlinks:
- History of the concepts of 'religion' and 'science'
- Perspectives
- Bahá'í
- Buddhism
- Christianity
- Confucianism and traditional Chinese religion
- Hinduism
- Islam
- Jainism
- Perspectives from the scientific community
- Public perceptions of science
- See also:
- Conflict thesis
- Continuity thesis
- Deep ecology
- Demarcation problem
- Faith and rationality
- Issues in Science and Religion
- List of scholars on the relationship between religion and science
- Merton thesis
- Natural theology
- Philosophy of science
- Politicization of science
- Religious skepticism
- Psychology of religion
- Scientific method and religion
- Theistic evolution
- By tradition:
- In the US:
Neuroscience, Neurology and the Central Nervous System
YouTube Video: Introduction to Neuroscience (Stanford University)
Pictured: Illustration of the Central Nervous System
Neuroscience also referred to as "Neural Science" is the scientific study of the nervous system.
Traditionally, neuroscience is recognized as a branch of biology. However, it is currently an interdisciplinary science that collaborates with other fields such as:
Neuroscience also exerts influence on other fields, such as neuroeducation, neuroethics, and neurolaw.
The term neurobiology is often used interchangeably with the term neuroscience, although the former refers specifically to the biology of the nervous system, whereas the latter refers to the entire science of the nervous system (thus can include elements of psychology as well as the purely physical sciences).
The scope of neuroscience has broadened to include different approaches used to study the:
The techniques used by neuroscientists have also expanded enormously, from molecular and cellular studies of individual nerve cells to imaging of sensory and motor tasks in the brain. Recent theoretical advances in neuroscience have also been aided by the study of neural networks.
As a result of the increasing number of scientists who study the nervous system, several prominent neuroscience organizations have been formed to provide a forum to all neuroscientists and educators.
For example,
Click here for further amplification about Neuroscience.
___________________________________________________________________________
Neurology is a branch of medicine dealing with disorders of the nervous system.
Neurology deals with the diagnosis and treatment of all categories of conditions and disease involving the central and peripheral nervous system (and its subdivisions, the autonomic nervous system and the somatic nervous system); including their coverings, blood vessels, and all effector tissue, such as muscle.
Neurological practice relies heavily on the field of neuroscience, which is the scientific study of the nervous system.
A neurologist is a physician specializing in neurology and trained to investigate, or diagnose and treat neurological disorders. Neurologists may also be involved in clinical research, clinical trials, and basic or translational research. While neurology is a non-surgical specialty, its corresponding surgical specialty is neurosurgery.
Click here for further amplification about Neurology.
___________________________________________________________________________
The Central Nervous System (CNS) is the part of the nervous system consisting of the brain and spinal cord. The central nervous system is so named because it integrates information it receives from, and coordinates and influences the activity of, all parts of the bodies of bilaterally symmetric animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish—and it contains the majority of the nervous system.
Many consider the retina and the optic nerve (2nd cranial nerve), as well as the olfactory nerves (1st) and olfactory epithelium as parts of the CNS, synapsing directly on brain tissue without intermediate ganglia.
Following this classification the olfactory epithelium is the only central nervous tissue in direct contact with the environment, which opens up for therapeutic treatments. The CNS is contained within the dorsal body cavity, with the brain housed in the cranial cavity and the spinal cord in the spinal canal. In vertebrates, the brain is protected by the skull, while the spinal cord is protected by the vertebrae, both enclosed in the meninges.
Click here for further amplification about the Central Nervous System.
Traditionally, neuroscience is recognized as a branch of biology. However, it is currently an interdisciplinary science that collaborates with other fields such as:
- chemistry,
- cognitive science,
- computer science,
- engineering,
- linguistics,
- mathematics,
- medicine (including neurology),
- genetics,
- and allied disciplines including philosophy, physics, and psychology.
Neuroscience also exerts influence on other fields, such as neuroeducation, neuroethics, and neurolaw.
The term neurobiology is often used interchangeably with the term neuroscience, although the former refers specifically to the biology of the nervous system, whereas the latter refers to the entire science of the nervous system (thus can include elements of psychology as well as the purely physical sciences).
The scope of neuroscience has broadened to include different approaches used to study the:
- molecular,
- cellular,
- developmental,
- structural,
- functional,
- evolutionary,
- computational,
- and medical aspects of the nervous system.
The techniques used by neuroscientists have also expanded enormously, from molecular and cellular studies of individual nerve cells to imaging of sensory and motor tasks in the brain. Recent theoretical advances in neuroscience have also been aided by the study of neural networks.
As a result of the increasing number of scientists who study the nervous system, several prominent neuroscience organizations have been formed to provide a forum to all neuroscientists and educators.
For example,
- the International Brain Research Organization was founded in 1960,
- the International Society for Neurochemistry in 1963,
- the European Brain and Behaviour Society in 1968,
- and the Society for Neuroscience in 1969.
Click here for further amplification about Neuroscience.
___________________________________________________________________________
Neurology is a branch of medicine dealing with disorders of the nervous system.
Neurology deals with the diagnosis and treatment of all categories of conditions and disease involving the central and peripheral nervous system (and its subdivisions, the autonomic nervous system and the somatic nervous system); including their coverings, blood vessels, and all effector tissue, such as muscle.
Neurological practice relies heavily on the field of neuroscience, which is the scientific study of the nervous system.
A neurologist is a physician specializing in neurology and trained to investigate, or diagnose and treat neurological disorders. Neurologists may also be involved in clinical research, clinical trials, and basic or translational research. While neurology is a non-surgical specialty, its corresponding surgical specialty is neurosurgery.
Click here for further amplification about Neurology.
___________________________________________________________________________
The Central Nervous System (CNS) is the part of the nervous system consisting of the brain and spinal cord. The central nervous system is so named because it integrates information it receives from, and coordinates and influences the activity of, all parts of the bodies of bilaterally symmetric animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish—and it contains the majority of the nervous system.
Many consider the retina and the optic nerve (2nd cranial nerve), as well as the olfactory nerves (1st) and olfactory epithelium as parts of the CNS, synapsing directly on brain tissue without intermediate ganglia.
Following this classification the olfactory epithelium is the only central nervous tissue in direct contact with the environment, which opens up for therapeutic treatments. The CNS is contained within the dorsal body cavity, with the brain housed in the cranial cavity and the spinal cord in the spinal canal. In vertebrates, the brain is protected by the skull, while the spinal cord is protected by the vertebrae, both enclosed in the meninges.
Click here for further amplification about the Central Nervous System.
The Interrelationships between Weather, Meteorology and Climate Change over Time.
YouTube Video: Predicting Weather
(NASA Connect segment explaining how scientists use satellites to predict weather. The segment explores the Afternoon Constellation, or the collection of satellites known as the 'A' Train as well as weather balloons, weather stations and local weather observers.)
Picture #1 (Below): 2015 – Warmest Global Year on Record (since 1880) – Colors indicate temperature anomalies (Courtesy of NASA/NOAA; 20 January 2016).
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy.
Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers to day-to-day temperature and precipitation activity, whereas climate is the term for the statistics of atmospheric conditions over longer periods of time. When used without qualification, "weather" is generally understood to mean the weather of Earth.
Weather is driven by air pressure, temperature and moisture differences between one place and another. These differences can occur due to the sun's angle at any particular spot, which varies by latitude from the tropics. The strong temperature contrast between polar and tropical air gives rise to the jet stream.
Weather systems in the mid-latitudes, such as extratropical cyclones, are caused by instabilities of the jet stream flow. Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at different angles at different times of the year. On Earth's surface, temperatures usually range ±40 °C (−40 °F to 100 °F) annually.
Over thousands of years, changes in Earth's orbit can affect the amount and distribution of solar energy received by the Earth, thus influencing long-term climate and global climate change.
Surface temperature differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes due to differences in compressional heating.
Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location. The system is a chaotic system; so small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to control the weather have occurred throughout human history, and there is evidence that human activities such as agriculture and industry have modified weather patterns.
Studying how the weather works on other planets has been helpful in understanding how weather works on Earth. A famous landmark in the Solar System, Jupiter's Great Red Spot, is an anticyclonic storm known to have existed for at least 300 years.
However, weather is not limited to planetary bodies. A star's corona is constantly being lost to space, creating what is essentially a very thin atmosphere throughout the Solar System. The movement of mass ejected from the Sun is known as solar wind.
For further amplification about Weather, click here.
___________________________________________________________________________
Meteorology is the interdisciplinary scientific study of the atmosphere. The study of meteorology dates back millennia, though significant progress in meteorology did not occur until the 18th century.
Picture #2 (Below): General Circulation of the Earth's Atmosphere: The westerlies and trade winds are part of the Earth's atmospheric circulation.
The 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data. It wasn't until after the elucidation of the laws of physics and, more particularly, the development of the computer, allowing for the automated solution of the great many equations that model the weather, in the latter half of the 20th century that significant breakthroughs in weather forecasting were achieved.
Meteorological phenomena are observable weather events that are explained by the science of meteorology. Meteorological phenomena are described and quantified by the variables of Earth's atmosphere: temperature, air pressure, water vapor, mass flow,
and the variations and interactions of those variables, and how they change over time.
Different spatial scales are used to describe and predict weather on local, regional, and global levels. Meteorology, climatology, atmospheric physics, and atmospheric chemistry are sub-disciplines of the atmospheric sciences.
Meteorology and hydrology compose the interdisciplinary field of hydrometeorology. The interactions between Earth's atmosphere and its oceans are part of a coupled ocean-atmosphere system.
Meteorology has application in many diverse fields such as the military, energy production, transport, agriculture, and construction.
For further amplification about Meteorology, click here.
___________________________________________________________________________
Climatology or climate science is the study of climate, scientifically defined as weather conditions averaged over a period of time.
Picture #3 (Below): Map of the average temperature over 30 years. Data sets formed from the long-term average of historical weather parameters are sometimes called a "climatology". (This image was created by Robert A. Rohde for Global Warming Art.)
This modern field of study is regarded as a branch of the atmospheric sciences and a subfield of physical geography, which is one of the Earth sciences.
Climatology now includes aspects of oceanography and biogeochemistry. Basic knowledge of climate can be used within shorter term weather forecasting using analog techniques such as,
Climate models are used for a variety of purposes from study of the dynamics of the weather and climate system to projections of future climate.
Click here for amplification on Climatology:
___________________________________________________________________________
Weather Forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century.
Weather forecasts are made by collecting quantitative data about the current state of the atmosphere at a given place and using scientific understanding of atmospheric processes to project how the atmosphere will change.
Once an all-human endeavor based mainly upon changes in barometric pressure, current weather conditions, and sky condition, weather forecasting now relies on computer-based models that take many atmospheric factors into account.
Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases.
The inaccuracy of forecasting is due to the chaotic nature of the atmosphere, the massive computational power required to solve the equations that describe the atmosphere, the error involved in measuring the initial conditions, and an incomplete understanding of atmospheric processes.
Hence, forecasts become less accurate as the difference between current time and the time for which the forecast is being made (the range of the forecast) increases. The use of ensembles and model consensus help narrow the error and pick the most likely outcome.
There are a variety of end uses to weather forecasts. Weather warnings are important forecasts because they are used to protect life and property. Forecasts based on temperature and precipitation are important to agriculture, and therefore to traders within commodity markets.
Temperature forecasts are used by utility companies to estimate demand over coming days. On an everyday basis, people use weather forecasts to determine what to wear on a given day. Since outdoor activities are severely curtailed by heavy rain, snow and wind chill, forecasts can be used to plan activities around these events, and to plan ahead and survive them.
Click Here for amplification about Weather Forecasting, including the means (and technology) used to forecast weather.
Climatology now includes aspects of oceanography and biogeochemistry. Basic knowledge of climate can be used within shorter term weather forecasting using analog techniques such as,
- the El Niño–Southern Oscillation (ENSO),
- the Madden–Julian oscillation (MJO),
- the North Atlantic oscillation (NAO),
- the Northern Annular Mode (NAM) which is also known as the Arctic oscillation (AO),
- the Northern Pacific (NP) Index,
- the Pacific decadal oscillation (PDO),
- and the Interdecadal Pacific Oscillation (IPO).
Climate models are used for a variety of purposes from study of the dynamics of the weather and climate system to projections of future climate.
Click here for amplification on Climatology:
___________________________________________________________________________
Weather Forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century.
Weather forecasts are made by collecting quantitative data about the current state of the atmosphere at a given place and using scientific understanding of atmospheric processes to project how the atmosphere will change.
Once an all-human endeavor based mainly upon changes in barometric pressure, current weather conditions, and sky condition, weather forecasting now relies on computer-based models that take many atmospheric factors into account.
Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases.
The inaccuracy of forecasting is due to the chaotic nature of the atmosphere, the massive computational power required to solve the equations that describe the atmosphere, the error involved in measuring the initial conditions, and an incomplete understanding of atmospheric processes.
Hence, forecasts become less accurate as the difference between current time and the time for which the forecast is being made (the range of the forecast) increases. The use of ensembles and model consensus help narrow the error and pick the most likely outcome.
There are a variety of end uses to weather forecasts. Weather warnings are important forecasts because they are used to protect life and property. Forecasts based on temperature and precipitation are important to agriculture, and therefore to traders within commodity markets.
Temperature forecasts are used by utility companies to estimate demand over coming days. On an everyday basis, people use weather forecasts to determine what to wear on a given day. Since outdoor activities are severely curtailed by heavy rain, snow and wind chill, forecasts can be used to plan activities around these events, and to plan ahead and survive them.
Click Here for amplification about Weather Forecasting, including the means (and technology) used to forecast weather.
Science and technology in the United States including a List of American Scientists
YouTube Video: Mayim Bialik* on 'The Big Bang Theory'** Inspiring Her New Book
* Mayim Bialik and **-The Big Bang Theory TV Sitcom
Pictured: Clockwise from upper left: Albert Einstein; Alexander Graham Bell, Thomas Edison, and Carl Sagan
Click here for an alphabetical List of American Scientists
The United States came into being around the Age of Enlightenment (circa 1680 to 1800), an era in Western philosophy in which writers and thinkers, rejecting the perceived superstitions of the past, instead chose to emphasize the intellectual, scientific and cultural life, centered upon the 18th century, in which reason was advocated as the primary source for legitimacy and authority.
Enlightenment philosophers envisioned a "republic of science," where ideas would be exchanged freely and useful knowledge would improve the lot of all citizens.
The United States Constitution itself reflects the desire to encourage scientific creativity. It gives the United States Congress the power "to promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries."
This clause formed the basis for the U.S. patent and copyright systems, whereby creators of original art and technology would get a government granted monopoly, which after a limited period would become free to all citizens, thereby enriching the public domain.
Click on any of the following blue hyperlinks for more about Science and Technology in the United States:
The United States came into being around the Age of Enlightenment (circa 1680 to 1800), an era in Western philosophy in which writers and thinkers, rejecting the perceived superstitions of the past, instead chose to emphasize the intellectual, scientific and cultural life, centered upon the 18th century, in which reason was advocated as the primary source for legitimacy and authority.
Enlightenment philosophers envisioned a "republic of science," where ideas would be exchanged freely and useful knowledge would improve the lot of all citizens.
The United States Constitution itself reflects the desire to encourage scientific creativity. It gives the United States Congress the power "to promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries."
This clause formed the basis for the U.S. patent and copyright systems, whereby creators of original art and technology would get a government granted monopoly, which after a limited period would become free to all citizens, thereby enriching the public domain.
Click on any of the following blue hyperlinks for more about Science and Technology in the United States:
- Early North American science
- Science immigration
- American applied science
- The Atomic Age and "Big Science"
- Telecom and technology
- The Space Age
- Medicine and health care
- See also:
- Science policy of the United States
- Biomedical research in the United States
- Technological and industrial history of the United States
- Timeline of United States inventions
- Timeline of United States discoveries
- List of African American inventors and scientists
- National Inventors Hall of Fame
- United States Patent and Trademark Office
- NASA spinoff technologies
- Yankee ingenuity
Thought Identification for Mind-reading Technology
YouTube Video from National Science Foundation: Mind Reading Computer System May Help People With Locked-in Syndrome
“Intel demos software that reads your mind: The software uses MRI brain scans to decipher which words you're mostly likely thinking about. In highly controlled situations, it achieves perfect scores.” By http://www.cnet.com/news/intel-demos-software-that-reads-your-mind/
Thought identification refers to the empirically verified use of technology to, in some sense, read people's minds. Advances in research have made this possible by using human neuroimaging to decode a person's conscious experience based on non-invasive measurements of an individual's brain activity.
Professor of neuropsychology Barbara Sahakian qualifies, "A lot of neuroscientists in the field are very cautious and say we can't talk about reading individuals' minds, and right now that is very true, but we're moving ahead so rapidly, it's not going to be that long before we will be able to tell whether someone's making up a story, or whether someone intended to do a crime with a certain degree of certainty."
History:
Psychologist John Dylan-Haynes experienced breakthroughs in brain imaging research in 2006 by using fMRI. This research included new findings on visual object recognition, tracking dynamic mental processes, lie detecting, and decoding unconscious processing. The combination of these four discoveries revealed such a significant amount of information about an individuals thoughts that Haynes termed it "brain reading."
The fMRI has allowed research to expand by significant amounts because it can track the activity in an individual's brain by measuring the brain's blood flow. It is currently thought to be the best method for measuring brain activity, which is why it has been used in multiple research experiments in order to improve the understanding of how doctors and psychologists can identify thoughts.
The term “thought identification” started being used in 2009 after neuroscientist Marcel Just coined it in a 60 Minutes interview. His reasoning for this term pertains to his overall goal of his research to "to see if they could identify exactly what happens in the brain when people think specific thoughts."
Examples:
Identifying thoughts
When humans think of an object, such as a screwdriver, many different areas of the brain activate. Marcel Just and his colleague, Tom Mitchell, have used fMRI brain scans to teach a computer to identify the various parts of the brain associated with specific thoughts.
This technology also yielded a discovery: similar thoughts in different human brains are surprisingly similar neurologically. To illustrate this, Just and Mitchell used their computer to predict, based on nothing but fMRI data, which of several images a volunteer was thinking about. The computer was 100% accurate, but so far the machine is only distinguishing between 10 images.
John-Dylan Haynes states that fMRI can also be used to identify recognition in the brain. He provides the example of a criminal being interrogated about whether he recognizes the scene of the crime or murder weapons.
Just and Mitchell also claim they are beginning to be able to identify kindness, hypocrisy, and love in the brain.
In 2008 IBM applied for a patent on how to extract mental images of human faces from the human brain. It uses a feedback loop based on brain measurements of the fusiform gyrus area in the brain which activates proportionate with degree of facial recognition.
In 2011, a team led by Shinji Nishimoto used only brain recordings to partially reconstruct what volunteers were seeing. The researchers applied a new model, about how moving object information is processed in human brains, while volunteers watched clips from several videos.
An algorithm searched through thousands of hours of external YouTube video footage (none of the videos were the same as the ones the volunteers watched) to select the clips that were most similar. The authors have uploaded demos comparing the watched and the computer-estimated videos.
Predicting intentions:
See also: Neuroscience of free will
Some researchers in 2008 were able to predict, with 60% accuracy, whether a subject was going to push a button with their left or right hand. This is notable, not just because the accuracy is better than chance, but also because the scientists were able to make these predictions up to 10 seconds before the subject acted - well before the subject felt they had decided. This data is even more striking in light of other research suggesting that the decision to move, and possibly the ability to cancel that movement at the last second, may be the results of unconscious processing.
John Dylan-Haynes has also demonstrated that fMRI can be used to identify whether a volunteer is about to add or subtract two numbers in their head.
Reading thoughts before they are voiced:
December 16, 2015, a research conducted by Toshimasa Yamazaki at Kyushu Institute of Technology found using Rock-paper-scissors game a computer is able to determine a choice made by the subjects before they move a hand. An EEG was use to measure activity in the Broca's area to see the words two seconds before the words were uttered.
Brain as input device
Emotiv Systems, an Australian electronics company, has demonstrated a headset that can be trained to recognize a user's thought patterns for different commands. Tan Le demonstrated the headset's ability to manipulate virtual objects on screen, and discussed various future applications for such brain-computer interface devices, from powering wheel chairs to replacing the mouse and keyboard.
Decoding brain activity to reconstruct words
On 31 January 2012 Brian Pasley and colleagues of University of California Berkeley published their paper in PLoS Biology wherein subjects' internal neural processing of auditory information was decoded and reconstructed as sound on computer by gathering and analyzing electrical signals directly from subjects' brains.
The research team conducted their studies on the superior temporal gyrus, a region of the brain that is involved in higher order neural processing to make semantic sense from auditory information.
The research team used a computer model to analyze various parts of the brain that might be involved in neural firing while processing auditory signals. Using the computational model, scientists were able to identify the brain activity involved in processing auditory information when subjects were presented with recording of individual words.
Later, the computer model of auditory information processing was used to reconstruct some of the words back into sound based on the neural processing of the subjects. However the reconstructed sounds were not of good quality and could be recognized only when the audio wave patterns of the reconstructed sound were visually matched with the audio wave patterns of the original sound that was presented to the subjects.
However this research marks a direction towards more precise identification of neural activity in cognition.
Recognizing brain waves in security
In 2013 a project led by University of California Berkeley professor John Chuang published findings on the feasibility of brainwave-based computer authentication as a substitute for passwords. Improvements in the use of biometrics for computer authentication has continually improved since the 1980s, but this research team was looking for a method faster and less intrusive than today's retina scans, fingerprinting, and voice recognition.
The technology chosen to improve security measures is an electroencephalogram (EEG), or brainwave measurer, to improve passwords into "pass thoughts." Using this method Chuang and his team were able to customize tasks and their authentication thresholds to the point where they were able to reduce error rates under 1%, significantly better than other recent methods. In order to better attract users to this new form of security the team is still researching mental tasks that are enjoyable for the user to perform while having their brainwaves identified. In the future this method could be as cheap, accessible, and straightforward as thought itself.
Ethical issues
With brain scanning technology becoming increasingly accurate, experts predict important debates over how and when it should be used. One potential area of application is criminal law. Haynes states that simply refusing to use brain scans on suspects also prevents the wrongly accused from proving their innocence.
It has been argued that allowing brain scans in the United States would violate the 5th Amendment's right to not self incriminate. The important question is whether brain imaging is like testimony, or instead like DNA, blood, or semen. Paul Root Wolpe, director of the Center for Ethics at Emory University in Atlanta predicts that this question will be decided by a Supreme Court case.
In other countries outside the United States, thought Identification has already been used in criminal law. In 2008 an Indian woman was convicted of murder after an EEG of her brain allegedly revealed that she was familiar with the circumstances surrounding the poisoning of her ex-fiancé. Some neuroscientists and legal scholars doubt the validity of using thought identification as a whole for anything past research on the nature of deception and the brain.
Future researchExperts are unsure of how far thought identification can expand, but Marcel Just believes that in 3–5 years there will be a machine that is able to read complex thoughts such as 'I hate so-and-so'.
Dr. Donald Marks, founder and chief science officer of MMT, is working on playing back thoughts individuals have after they have already been recorded.
Researchers at the University of California Berkeley have already been successful in forming, erasing, and reactivating memories in rats. Dr. Marks says they are working on applying the same techniques to humans. This discovery could be monumental for war veterans who suffer from PTSD.
Further research is also being done in analyzing brain activity during video games to detect criminals, neuromarketing, and using brain scans in government security checks.
See also
Professor of neuropsychology Barbara Sahakian qualifies, "A lot of neuroscientists in the field are very cautious and say we can't talk about reading individuals' minds, and right now that is very true, but we're moving ahead so rapidly, it's not going to be that long before we will be able to tell whether someone's making up a story, or whether someone intended to do a crime with a certain degree of certainty."
History:
Psychologist John Dylan-Haynes experienced breakthroughs in brain imaging research in 2006 by using fMRI. This research included new findings on visual object recognition, tracking dynamic mental processes, lie detecting, and decoding unconscious processing. The combination of these four discoveries revealed such a significant amount of information about an individuals thoughts that Haynes termed it "brain reading."
The fMRI has allowed research to expand by significant amounts because it can track the activity in an individual's brain by measuring the brain's blood flow. It is currently thought to be the best method for measuring brain activity, which is why it has been used in multiple research experiments in order to improve the understanding of how doctors and psychologists can identify thoughts.
The term “thought identification” started being used in 2009 after neuroscientist Marcel Just coined it in a 60 Minutes interview. His reasoning for this term pertains to his overall goal of his research to "to see if they could identify exactly what happens in the brain when people think specific thoughts."
Examples:
Identifying thoughts
When humans think of an object, such as a screwdriver, many different areas of the brain activate. Marcel Just and his colleague, Tom Mitchell, have used fMRI brain scans to teach a computer to identify the various parts of the brain associated with specific thoughts.
This technology also yielded a discovery: similar thoughts in different human brains are surprisingly similar neurologically. To illustrate this, Just and Mitchell used their computer to predict, based on nothing but fMRI data, which of several images a volunteer was thinking about. The computer was 100% accurate, but so far the machine is only distinguishing between 10 images.
John-Dylan Haynes states that fMRI can also be used to identify recognition in the brain. He provides the example of a criminal being interrogated about whether he recognizes the scene of the crime or murder weapons.
Just and Mitchell also claim they are beginning to be able to identify kindness, hypocrisy, and love in the brain.
In 2008 IBM applied for a patent on how to extract mental images of human faces from the human brain. It uses a feedback loop based on brain measurements of the fusiform gyrus area in the brain which activates proportionate with degree of facial recognition.
In 2011, a team led by Shinji Nishimoto used only brain recordings to partially reconstruct what volunteers were seeing. The researchers applied a new model, about how moving object information is processed in human brains, while volunteers watched clips from several videos.
An algorithm searched through thousands of hours of external YouTube video footage (none of the videos were the same as the ones the volunteers watched) to select the clips that were most similar. The authors have uploaded demos comparing the watched and the computer-estimated videos.
Predicting intentions:
See also: Neuroscience of free will
Some researchers in 2008 were able to predict, with 60% accuracy, whether a subject was going to push a button with their left or right hand. This is notable, not just because the accuracy is better than chance, but also because the scientists were able to make these predictions up to 10 seconds before the subject acted - well before the subject felt they had decided. This data is even more striking in light of other research suggesting that the decision to move, and possibly the ability to cancel that movement at the last second, may be the results of unconscious processing.
John Dylan-Haynes has also demonstrated that fMRI can be used to identify whether a volunteer is about to add or subtract two numbers in their head.
Reading thoughts before they are voiced:
December 16, 2015, a research conducted by Toshimasa Yamazaki at Kyushu Institute of Technology found using Rock-paper-scissors game a computer is able to determine a choice made by the subjects before they move a hand. An EEG was use to measure activity in the Broca's area to see the words two seconds before the words were uttered.
Brain as input device
Emotiv Systems, an Australian electronics company, has demonstrated a headset that can be trained to recognize a user's thought patterns for different commands. Tan Le demonstrated the headset's ability to manipulate virtual objects on screen, and discussed various future applications for such brain-computer interface devices, from powering wheel chairs to replacing the mouse and keyboard.
Decoding brain activity to reconstruct words
On 31 January 2012 Brian Pasley and colleagues of University of California Berkeley published their paper in PLoS Biology wherein subjects' internal neural processing of auditory information was decoded and reconstructed as sound on computer by gathering and analyzing electrical signals directly from subjects' brains.
The research team conducted their studies on the superior temporal gyrus, a region of the brain that is involved in higher order neural processing to make semantic sense from auditory information.
The research team used a computer model to analyze various parts of the brain that might be involved in neural firing while processing auditory signals. Using the computational model, scientists were able to identify the brain activity involved in processing auditory information when subjects were presented with recording of individual words.
Later, the computer model of auditory information processing was used to reconstruct some of the words back into sound based on the neural processing of the subjects. However the reconstructed sounds were not of good quality and could be recognized only when the audio wave patterns of the reconstructed sound were visually matched with the audio wave patterns of the original sound that was presented to the subjects.
However this research marks a direction towards more precise identification of neural activity in cognition.
Recognizing brain waves in security
In 2013 a project led by University of California Berkeley professor John Chuang published findings on the feasibility of brainwave-based computer authentication as a substitute for passwords. Improvements in the use of biometrics for computer authentication has continually improved since the 1980s, but this research team was looking for a method faster and less intrusive than today's retina scans, fingerprinting, and voice recognition.
The technology chosen to improve security measures is an electroencephalogram (EEG), or brainwave measurer, to improve passwords into "pass thoughts." Using this method Chuang and his team were able to customize tasks and their authentication thresholds to the point where they were able to reduce error rates under 1%, significantly better than other recent methods. In order to better attract users to this new form of security the team is still researching mental tasks that are enjoyable for the user to perform while having their brainwaves identified. In the future this method could be as cheap, accessible, and straightforward as thought itself.
Ethical issues
With brain scanning technology becoming increasingly accurate, experts predict important debates over how and when it should be used. One potential area of application is criminal law. Haynes states that simply refusing to use brain scans on suspects also prevents the wrongly accused from proving their innocence.
It has been argued that allowing brain scans in the United States would violate the 5th Amendment's right to not self incriminate. The important question is whether brain imaging is like testimony, or instead like DNA, blood, or semen. Paul Root Wolpe, director of the Center for Ethics at Emory University in Atlanta predicts that this question will be decided by a Supreme Court case.
In other countries outside the United States, thought Identification has already been used in criminal law. In 2008 an Indian woman was convicted of murder after an EEG of her brain allegedly revealed that she was familiar with the circumstances surrounding the poisoning of her ex-fiancé. Some neuroscientists and legal scholars doubt the validity of using thought identification as a whole for anything past research on the nature of deception and the brain.
Future researchExperts are unsure of how far thought identification can expand, but Marcel Just believes that in 3–5 years there will be a machine that is able to read complex thoughts such as 'I hate so-and-so'.
Dr. Donald Marks, founder and chief science officer of MMT, is working on playing back thoughts individuals have after they have already been recorded.
Researchers at the University of California Berkeley have already been successful in forming, erasing, and reactivating memories in rats. Dr. Marks says they are working on applying the same techniques to humans. This discovery could be monumental for war veterans who suffer from PTSD.
Further research is also being done in analyzing brain activity during video games to detect criminals, neuromarketing, and using brain scans in government security checks.
See also
Institute of Electrical and Electronics Engineers (IEEE)
YouTube Video: Meet the IEEE Standards Association
The Institute of Electrical and Electronics Engineers (IEEE, pronounced "I triple E") is a professional association with its corporate office in New York City and its operations center in Piscataway, New Jersey. It was formed in 1963 from the amalgamation of the American Institute of Electrical Engineers and the Institute of Radio Engineers.
Today, IEEE is the world's largest association of technical professionals with more than 420,000 members in over 160 countries around the world. Its objectives are the educational and technical advancement of electrical and electronic engineering, telecommunications, computer engineering and allied disciplines.
IEEE stands for the "Institute of Electrical and Electronics Engineers". The association is chartered under this full legal name. IEEE's membership has long been composed of engineers and scientists.
Allied professionals who are members include computer scientists, software developers, information technology professionals, physicists, and medical doctors, in addition to IEEE's electrical and electronics engineering core. For this reason the organization no longer goes by the full name, except on legal business documents, and is referred to simply as IEEE.
The IEEE is dedicated to advancing technological innovation and excellence. It has about 420,000 members in about 160 countries, slightly less than half of whom reside in the United States.
The IEEE is incorporated under the Not-for-Profit Corporation Law of the state of New York. It was formed in 1963 by the merger of the Institute of Radio Engineers (IRE, founded 1912) and the American Institute of Electrical Engineers (AIEE, founded 1884).
The IEEE serves as a major publisher of scientific journals and organizer of conferences, workshops, and symposia (many of which have associated published proceedings). It is also a leading standards development organization for the development of industrial standards (having developed over 900 active industry technical standards) in a broad range of disciplines, including:
IEEE develops and participates in educational activities such as accreditation of electrical engineering programs in institutes of higher learning. The IEEE logo is a diamond-shaped design which illustrates the right hand grip rule embedded in Benjamin Franklin's kite, and it was created at the time of the 1963 merger.
IEEE has a dual complementary regional and technical structure – with organizational units based on geography (e.g., the IEEE Philadelphia Section, the IEEE Buenaventura Section, IEEE South Africa Section) and technical focus (e.g., the IEEE Computer Society). It manages a separate organizational unit (IEEE-USA) which recommends policies and implements programs specifically intended to benefit the members, the profession and the public in the United States.
The IEEE includes 39 technical Societies, organized around specialized technical fields, with more than 300 local organizations that hold regular meetings.
The IEEE Standards Association is in charge of the standardization activities of the IEEE.
The IEEE History Center became a feeder organization to the Engineering and Technology History Wiki (ETHW) in 2015.
The new ETHW is a cooperative effort by various engineering societies as a formal repository of topic articles, oral histories, first-hand histories, Landmarks + Milestones and archival documents. The IEEE History Center is annexed to Stevens University Hoboken, NJ.
In 2016, the IEEE acquired GlobalSpec, adding the provision of engineering data for a profit to its organizational portfolio.
Click on any of the following blue hyperlinks for more about IEEE:
Today, IEEE is the world's largest association of technical professionals with more than 420,000 members in over 160 countries around the world. Its objectives are the educational and technical advancement of electrical and electronic engineering, telecommunications, computer engineering and allied disciplines.
IEEE stands for the "Institute of Electrical and Electronics Engineers". The association is chartered under this full legal name. IEEE's membership has long been composed of engineers and scientists.
Allied professionals who are members include computer scientists, software developers, information technology professionals, physicists, and medical doctors, in addition to IEEE's electrical and electronics engineering core. For this reason the organization no longer goes by the full name, except on legal business documents, and is referred to simply as IEEE.
The IEEE is dedicated to advancing technological innovation and excellence. It has about 420,000 members in about 160 countries, slightly less than half of whom reside in the United States.
The IEEE is incorporated under the Not-for-Profit Corporation Law of the state of New York. It was formed in 1963 by the merger of the Institute of Radio Engineers (IRE, founded 1912) and the American Institute of Electrical Engineers (AIEE, founded 1884).
The IEEE serves as a major publisher of scientific journals and organizer of conferences, workshops, and symposia (many of which have associated published proceedings). It is also a leading standards development organization for the development of industrial standards (having developed over 900 active industry technical standards) in a broad range of disciplines, including:
- electric power and energy,
- biomedical technology and healthcare,
- information technology,
- information assurance,
- telecommunications, consumer
- electronics,
- transportation,
- aerospace,
- and nanotechnology.
IEEE develops and participates in educational activities such as accreditation of electrical engineering programs in institutes of higher learning. The IEEE logo is a diamond-shaped design which illustrates the right hand grip rule embedded in Benjamin Franklin's kite, and it was created at the time of the 1963 merger.
IEEE has a dual complementary regional and technical structure – with organizational units based on geography (e.g., the IEEE Philadelphia Section, the IEEE Buenaventura Section, IEEE South Africa Section) and technical focus (e.g., the IEEE Computer Society). It manages a separate organizational unit (IEEE-USA) which recommends policies and implements programs specifically intended to benefit the members, the profession and the public in the United States.
The IEEE includes 39 technical Societies, organized around specialized technical fields, with more than 300 local organizations that hold regular meetings.
The IEEE Standards Association is in charge of the standardization activities of the IEEE.
The IEEE History Center became a feeder organization to the Engineering and Technology History Wiki (ETHW) in 2015.
The new ETHW is a cooperative effort by various engineering societies as a formal repository of topic articles, oral histories, first-hand histories, Landmarks + Milestones and archival documents. The IEEE History Center is annexed to Stevens University Hoboken, NJ.
In 2016, the IEEE acquired GlobalSpec, adding the provision of engineering data for a profit to its organizational portfolio.
Click on any of the following blue hyperlinks for more about IEEE:
- History
- Current Leadership
- Publications
- Educational activities
- IEEE Conferences
- Standards and development process
- Membership and member grades
- Awards
- Societies
- Technical councils
- Technical committees
- Organizational units
- IEEE Foundation
- See also:
- Glossary of electrical and electronics engineering
- Certified Software Development Professional (CSDP) Program of the IEEE Computer Society
- Eta Kappa Nu, the electrical and computer engineering honor society of the IEEE
- Institution of Engineering and Technology
- How many SCIgen papers in Computer Science?
- IEEE Cloud Computing
- Official IEEE website
- Engineering and Technology History Wiki – a Mediawiki-based website containing information about the history of various engineering societies, including IEEE, its members, their professions, and their technologies.
- IEEE Xplore – the IEEE Xplore Digital Library, with over 2.6 million technical documents available online for purchase.
- IEEE.tv – a video content website operated by the IEEE.
- IEEE Fellows Directory – A comprehensive online directory of IEEE Fellows.
- IEEE eLearning Library – an online library of more than 200 self-study multimedia short courses and tutorials in technical fields of interest to the IEEE.
Scientific Method
YouTube Video about Scientific Method
Pictured below: The scientific method is a never ending cycle of hypothesis, prediction, testing and questioning
The Oxford Dictionaries Online defines the scientific method as "a method or procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses". Experiments are a procedure designed to test hypotheses. Experiments are an important tool of the scientific method. To be termed scientific, a method of inquiry is commonly based on empirical or measurable evidence subject to specific principles of reasoning.
Though there are diverse models for the scientific method available, in general there is a continuous process that includes observations about the natural world. People are naturally inquisitive, so they often come up with questions about things they see or hear, and they often develop ideas or hypotheses about why things are the way they are. The best hypotheses lead to predictions that can be tested in various ways. The most conclusive testing of hypotheses comes from reasoning based on carefully controlled experimental data.
Depending on how well additional tests match the predictions, the original hypothesis may require refinement, alteration, expansion or even rejection. If a particular hypothesis becomes very well supported, a general theory may be developed.
Although procedures vary from one field of inquiry to another, they are frequently the same from one to another. The process of the scientific method involves making conjectures (hypotheses), deriving predictions from them as logical consequences, and then carrying out experiments or empirical observations based on those predictions.
A hypothesis is a conjecture, based on knowledge obtained while seeking answers to the question. The hypothesis might be very specific, or it might be broad. Scientists then test hypotheses by conducting experiments or studies. A scientific hypothesis must be falsifiable, implying that it is possible to identify a possible outcome of an experiment or observation that conflicts with predictions deduced from the hypothesis; otherwise, the hypothesis cannot be meaningfully tested.
The purpose of an experiment is to determine whether observations agree with or conflict with the predictions derived from a hypothesis. Experiments can take place anywhere from a garage to CERN's Large Hadron Collider. There are difficulties in a formulaic statement of method, however.
Though the scientific method is often presented as a fixed sequence of steps, it represents rather a set of general principles. Not all steps take place in every scientific inquiry (nor to the same degree), and they are not always in the same order.
Some philosophers and scientists have argued that there is no scientific method; they include physicist Lee Smolin and philosopher Paul Feyerabend (in his Against Method). Robert Nola and Howard Sankey remark that "For some, the whole idea of a theory of scientific method is yester-year's debate, the continuation of which can be summed up as yet more of the proverbial deceased equine castigation. We beg to differ."
Click on any of the following blue hyperlinks for more about Scientific Method:
Though there are diverse models for the scientific method available, in general there is a continuous process that includes observations about the natural world. People are naturally inquisitive, so they often come up with questions about things they see or hear, and they often develop ideas or hypotheses about why things are the way they are. The best hypotheses lead to predictions that can be tested in various ways. The most conclusive testing of hypotheses comes from reasoning based on carefully controlled experimental data.
Depending on how well additional tests match the predictions, the original hypothesis may require refinement, alteration, expansion or even rejection. If a particular hypothesis becomes very well supported, a general theory may be developed.
Although procedures vary from one field of inquiry to another, they are frequently the same from one to another. The process of the scientific method involves making conjectures (hypotheses), deriving predictions from them as logical consequences, and then carrying out experiments or empirical observations based on those predictions.
A hypothesis is a conjecture, based on knowledge obtained while seeking answers to the question. The hypothesis might be very specific, or it might be broad. Scientists then test hypotheses by conducting experiments or studies. A scientific hypothesis must be falsifiable, implying that it is possible to identify a possible outcome of an experiment or observation that conflicts with predictions deduced from the hypothesis; otherwise, the hypothesis cannot be meaningfully tested.
The purpose of an experiment is to determine whether observations agree with or conflict with the predictions derived from a hypothesis. Experiments can take place anywhere from a garage to CERN's Large Hadron Collider. There are difficulties in a formulaic statement of method, however.
Though the scientific method is often presented as a fixed sequence of steps, it represents rather a set of general principles. Not all steps take place in every scientific inquiry (nor to the same degree), and they are not always in the same order.
Some philosophers and scientists have argued that there is no scientific method; they include physicist Lee Smolin and philosopher Paul Feyerabend (in his Against Method). Robert Nola and Howard Sankey remark that "For some, the whole idea of a theory of scientific method is yester-year's debate, the continuation of which can be summed up as yet more of the proverbial deceased equine castigation. We beg to differ."
Click on any of the following blue hyperlinks for more about Scientific Method:
- Overview
- Scientific inquiry
- Elements of the scientific method
- Models of scientific inquiry
- Communication and community
- Philosophy and sociology of science
- Role of chance in discovery
- History
- Relationship with mathematics
- See also:
Scientific Theory, including a List of Scientific Theories
YouTube Video: What’s the difference between a scientific law and theory?
-By Matt Anticole TedEd
Click here for a List of Scientific Theories.
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested, in accordance with the scientific method, using a predefined protocol of observation and experiment. Established scientific theories have withstood rigorous scrutiny and embody scientific knowledge.
The definition of a scientific theory (often contracted to "theory" for the sake of brevity) as used in the disciplines of science is significantly different from the common vernacular usage of the word "theory".
In everyday speech, "theory" can imply that something is an unsubstantiated and speculative guess, the opposite of its meaning in science. These different usages are comparable to the opposing usages of "prediction" in science versus everyday speech, where it denotes a mere hope.
The strength of a scientific theory is related to the diversity of phenomena it can explain and its simplicity. As additional scientific evidence is gathered, a scientific theory may be modified and ultimately rejected if it cannot be made to fit the new findings; in such circumstances, a more accurate theory is then required. In certain cases, the less-accurate unmodified scientific theory can still be treated as a theory if it is useful (due to its sheer simplicity) as an approximation under specific conditions.
A case in point is Newton's laws of motion, which can serve as an approximation to special relativity at velocities that are small relative to the speed of light.
Scientific theories are testable and make falsifiable predictions. They describe the causes of a particular natural phenomenon and are used to explain and predict aspects of the physical universe or specific areas of inquiry (for example, electricity, chemistry, and astronomy). Scientists use theories to further scientific knowledge, as well as to facilitate advances in technology or medicine.
As with other forms of scientific knowledge, scientific theories are both deductive and inductive, aiming for predictive and explanatory power.
The paleontologist Stephen Jay Gould wrote that "...facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world′s data. Theories are structures of ideas that explain and interpret facts."
Click on any of the following blue hyperlinks for more about Scientific Theory:
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested, in accordance with the scientific method, using a predefined protocol of observation and experiment. Established scientific theories have withstood rigorous scrutiny and embody scientific knowledge.
The definition of a scientific theory (often contracted to "theory" for the sake of brevity) as used in the disciplines of science is significantly different from the common vernacular usage of the word "theory".
In everyday speech, "theory" can imply that something is an unsubstantiated and speculative guess, the opposite of its meaning in science. These different usages are comparable to the opposing usages of "prediction" in science versus everyday speech, where it denotes a mere hope.
The strength of a scientific theory is related to the diversity of phenomena it can explain and its simplicity. As additional scientific evidence is gathered, a scientific theory may be modified and ultimately rejected if it cannot be made to fit the new findings; in such circumstances, a more accurate theory is then required. In certain cases, the less-accurate unmodified scientific theory can still be treated as a theory if it is useful (due to its sheer simplicity) as an approximation under specific conditions.
A case in point is Newton's laws of motion, which can serve as an approximation to special relativity at velocities that are small relative to the speed of light.
Scientific theories are testable and make falsifiable predictions. They describe the causes of a particular natural phenomenon and are used to explain and predict aspects of the physical universe or specific areas of inquiry (for example, electricity, chemistry, and astronomy). Scientists use theories to further scientific knowledge, as well as to facilitate advances in technology or medicine.
As with other forms of scientific knowledge, scientific theories are both deductive and inductive, aiming for predictive and explanatory power.
The paleontologist Stephen Jay Gould wrote that "...facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world′s data. Theories are structures of ideas that explain and interpret facts."
Click on any of the following blue hyperlinks for more about Scientific Theory:
- Types
- Characteristics
- Formation
- Modification and improvement
- Theories and laws
- About theories
- Descriptions
- In physics
Scientific Law including the Laws of Science as well as a List of Scientific Laws
YouTube Video: Fact vs. Theory vs. Hypothesis vs. Law… EXPLAINED!
Pictured below: Hypothesis, Theory & Law in Science
Click here for a List of Scientific Laws named after People.
A scientific law is a statement based on repeated experimental observations that describes some aspect of the universe.
A scientific law always applies under the same conditions, and implies that there is a causal relationship involving its elements. Factual and well-confirmed statements like "Mercury is liquid at standard temperature and pressure" are considered too specific to qualify as scientific laws.
A central problem in the philosophy of science, going back to David Hume, is that of distinguishing causal relationships (such as those implied by laws) from principles that arise due to constant conjunction.
Laws differ from scientific theories in that they do not posit a mechanism or explanation of phenomena: they are merely distillations of the results of repeated observation. As such, a law is limited in applicability to circumstances resembling those already observed, and may be found false when extrapolated.
Ohm's law only applies to linear networks, Newton's law of universal gravitation only applies in weak gravitational fields, the early laws of aerodynamics such as Bernoulli's principle do not apply in case of compressible flow such as occurs in transonic and supersonic flight,
Hooke's law only applies to strain below the elastic limit, etc. These laws remain useful, but only under the conditions where they apply.
Many laws take mathematical forms, and thus can be stated as an equation; for example, the law of conservation of energy can be written as "{\displaystyle \Delta E=0}", where E is the total amount of energy in the universe. Similarly, the first law of thermodynamics can be written as "{\displaystyle \mathrm {d} U=\delta Q-\delta W\,}".
The term "scientific law" is traditionally associated with the natural sciences, though the social sciences also contain laws. An example of a scientific law in social sciences is Zipf's law.
Like theories and hypotheses, laws make predictions (specifically, they predict that new observations will conform to the law), and can be falsified if they are found in contradiction with new data.
See also:
The laws of science, scientific laws, or scientific principles are statements that describe or predict a range of phenomena as they appear in nature. The term "law" has diverse usage in many cases: approximate, accurate, broad or narrow theories, in all natural scientific disciplines (physics, chemistry, biology, geology, astronomy etc.).
Scientific laws summarize and explain a large collection of facts determined by experiment, and are tested based on their ability to predict the results of future experiments. They are developed either from facts or through mathematics, and are strongly supported by empirical evidence. It is generally understood that they reflect causal relationships fundamental to reality, and are discovered rather than invented.
Laws reflect scientific knowledge that experiments have repeatedly verified (and never falsified). Their accuracy does not change when new theories are worked out, but rather the scope of application, since the equation (if any) representing the law does not change. As with other scientific knowledge, they do not have absolute certainty (as mathematical theorems or identities do), and it is always possible for a law to be overturned by future observations.
A law can usually be formulated as one or several statements or equations, so that it can be used to predict the outcome of an experiment, given the circumstances of the processes taking place.
Laws differ from hypotheses and postulates, which are proposed during the scientific process before and during validation by experiment and observation. These are not laws since they have not been verified to the same degree and may not be sufficiently general, although they may lead to the formulation of laws.
A law is a more solidified and formal statement, distilled from repeated experiment. Laws are narrower in scope than scientific theories, which may contain one or several laws. Unlike hypotheses, theories and laws may be simply referred to as scientific fact. Although the nature of a scientific law is a question in philosophy and although scientific laws describe nature mathematically, scientific laws are practical conclusions reached by the scientific method; they are intended to be neither laden with ontological commitments nor statements of logical absolutes.
According to the unity of science thesis, all scientific laws follow fundamentally from physics. Laws which occur in other sciences ultimately follow from physical laws. Often, from mathematically fundamental viewpoints, universal constants emerge from a scientific law.
Click on any of the following blue hyperlinks for more about the Laws of Science:
A scientific law is a statement based on repeated experimental observations that describes some aspect of the universe.
A scientific law always applies under the same conditions, and implies that there is a causal relationship involving its elements. Factual and well-confirmed statements like "Mercury is liquid at standard temperature and pressure" are considered too specific to qualify as scientific laws.
A central problem in the philosophy of science, going back to David Hume, is that of distinguishing causal relationships (such as those implied by laws) from principles that arise due to constant conjunction.
Laws differ from scientific theories in that they do not posit a mechanism or explanation of phenomena: they are merely distillations of the results of repeated observation. As such, a law is limited in applicability to circumstances resembling those already observed, and may be found false when extrapolated.
Ohm's law only applies to linear networks, Newton's law of universal gravitation only applies in weak gravitational fields, the early laws of aerodynamics such as Bernoulli's principle do not apply in case of compressible flow such as occurs in transonic and supersonic flight,
Hooke's law only applies to strain below the elastic limit, etc. These laws remain useful, but only under the conditions where they apply.
Many laws take mathematical forms, and thus can be stated as an equation; for example, the law of conservation of energy can be written as "{\displaystyle \Delta E=0}", where E is the total amount of energy in the universe. Similarly, the first law of thermodynamics can be written as "{\displaystyle \mathrm {d} U=\delta Q-\delta W\,}".
The term "scientific law" is traditionally associated with the natural sciences, though the social sciences also contain laws. An example of a scientific law in social sciences is Zipf's law.
Like theories and hypotheses, laws make predictions (specifically, they predict that new observations will conform to the law), and can be falsified if they are found in contradiction with new data.
See also:
- Empirical method
- Empirical research
- Empirical statistical laws
- Hypothesis
- Law (principle)
- Physical law
- Theory
The laws of science, scientific laws, or scientific principles are statements that describe or predict a range of phenomena as they appear in nature. The term "law" has diverse usage in many cases: approximate, accurate, broad or narrow theories, in all natural scientific disciplines (physics, chemistry, biology, geology, astronomy etc.).
Scientific laws summarize and explain a large collection of facts determined by experiment, and are tested based on their ability to predict the results of future experiments. They are developed either from facts or through mathematics, and are strongly supported by empirical evidence. It is generally understood that they reflect causal relationships fundamental to reality, and are discovered rather than invented.
Laws reflect scientific knowledge that experiments have repeatedly verified (and never falsified). Their accuracy does not change when new theories are worked out, but rather the scope of application, since the equation (if any) representing the law does not change. As with other scientific knowledge, they do not have absolute certainty (as mathematical theorems or identities do), and it is always possible for a law to be overturned by future observations.
A law can usually be formulated as one or several statements or equations, so that it can be used to predict the outcome of an experiment, given the circumstances of the processes taking place.
Laws differ from hypotheses and postulates, which are proposed during the scientific process before and during validation by experiment and observation. These are not laws since they have not been verified to the same degree and may not be sufficiently general, although they may lead to the formulation of laws.
A law is a more solidified and formal statement, distilled from repeated experiment. Laws are narrower in scope than scientific theories, which may contain one or several laws. Unlike hypotheses, theories and laws may be simply referred to as scientific fact. Although the nature of a scientific law is a question in philosophy and although scientific laws describe nature mathematically, scientific laws are practical conclusions reached by the scientific method; they are intended to be neither laden with ontological commitments nor statements of logical absolutes.
According to the unity of science thesis, all scientific laws follow fundamentally from physics. Laws which occur in other sciences ultimately follow from physical laws. Often, from mathematically fundamental viewpoints, universal constants emerge from a scientific law.
Click on any of the following blue hyperlinks for more about the Laws of Science:
- Conservation laws
- Laws of classical mechanics
- Laws of gravitation and relativity
- Thermodynamics
- Electromagnetism
- Photonics
- Laws of quantum mechanics
- Radiation laws
- Laws of chemistry
- Geophysical laws
- See also:
- Physics Formulary, a useful book in different formats containing many or the physical laws and formulae.
Introduction to Genetics
- YouTube Video: Genetics 101 | National Geographic
- YouTube Video: Genetics Basics | Chromosomes, Genes, DNA and Traits | Infinity Learn
- YouTube Video: Laws of Genetics - Lesson 5 | Don't Memorise
Genetics is the study of genes and tries to explain what they are and how they work. Genes are how living organisms inherit features or traits from their ancestors; for example, children usually look like their parents because they have inherited their parents' genes. Genetics tries to identify which traits are inherited and to explain how these traits are passed from generation to generation.
Some traits are part of an organism's physical appearance, such as eye color or height. Other sorts of traits are not easily seen and include blood types or resistance to diseases.
Some traits are inherited through genes, which is the reason why tall and thin people tend to have tall and thin children. Other traits come from interactions between genes and the environment, so a child who inherited the tendency of being tall will still be short if poorly nourished. The way our genes and environment interact to produce a trait can be complicated. For example, the chances of somebody dying of cancer or heart disease seems to depend on both their genes and their lifestyle.
Genes are made from a long molecule called DNA, which is copied and inherited across generations. DNA is made of simple units that line up in a particular order within it, carrying genetic information. The language used by DNA is called genetic code, which lets organisms read the information in the genes. This information is the instructions for the construction and operation of a living organism.
The information within a particular gene is not always exactly the same between one organism and another, so different copies of a gene do not always give exactly the same instructions. Each unique form of a single gene is called an allele. As an example, one allele for the gene for hair color could instruct the body to produce much pigment, producing black hair, while a different allele of the same gene might give garbled instructions that fail to produce any pigment, giving white hair.
Mutations are random changes in genes and can create new alleles. Mutations can also produce new traits, such as when mutations to an allele for black hair produce a new allele for white hair. This appearance of new traits is important in evolution.
Genes and inheritance
Genes are pieces of DNA that contain information for the synthesis of ribonucleic acids (RNAs) or polypeptides. Genes are inherited as units, with two parents dividing out copies of their genes to their offspring.
Humans have two copies of each of their genes, but each egg or sperm cell only gets one of those copies for each gene. An egg and sperm join to form a zygote with a complete set of genes. The resulting offspring has the same number of genes as their parents, but for any gene, one of their two copies comes from their father and one from their mother.
Example of mixing:
The effects of mixing depend on the types (the alleles) of the gene. If the father has two copies of an allele for red hair, and the mother has two copies for brown hair, all their children get the two alleles that give different instructions, one for red hair and one for brown.
The hair color of these children depends on how these alleles work together. If one allele dominates the instructions from another, it is called the dominant allele, and the allele that is overridden is called the recessive allele. In the case of a daughter with alleles for both red and brown hair, brown is dominant and she ends up with brown hair.
Although the red color allele is still there in this brown-haired girl, it doesn't show. This is a difference between what is seen on the surface (the traits of an organism, called its phenotype) and the genes within the organism (its genotype).
In this example, the allele for brown can be called "B" and the allele for red "b". (It is normal to write dominant alleles with capital letters and recessive ones with lower-case letters.) The brown hair daughter has the "brown hair phenotype" but her genotype is Bb, with one copy of the B allele, and one of the b allele.
Now imagine that this woman grows up and has children with a brown-haired man who also has a Bb genotype. Her eggs will be a mixture of two types, one sort containing the B allele, and one sort the b allele.
Similarly, her partner will produce a mix of two types of sperm containing one or the other of these two alleles. When the transmitted genes are joined up in their offspring, these children have a chance of getting either brown or red hair, since they could get a genotype of BB = brown hair, Bb = brown hair or bb = red hair. In this generation, there is, therefore, a chance of the recessive allele showing itself in the phenotype of the children—some of them may have red hair like their grandfather.
Many traits are inherited in a more complicated way than the example above. This can happen when there are several genes involved, each contributing a small part to the result.
Tall people tend to have tall children because their children get a package of many alleles that each contribute a bit to how much they grow. However, there are not clear groups of "short people" and "tall people", like there are groups of people with brown or red hair.
This is because of the large number of genes involved; this makes the trait very variable and people are of many different heights. Despite a common misconception, the green/blue eye traits are also inherited in this complex inheritance model.
Inheritance can also be complicated when the trait depends on the interaction between genetics and environment. For example, malnutrition does not change traits like eye color, but can stunt growth.
How genes work:
Genes make proteins:
Main article: Genetic code
The function of genes is to provide the information needed to make molecules called proteins in cells. Cells are the smallest independent parts of organisms: the human body contains about 100 trillion cells, while very small organisms like bacteria are just a single cell.
A cell is like a miniature and very complex factory that can make all the parts needed to produce a copy of itself, which happens when cells divide. There is a simple division of labor in cells—genes give instructions and proteins carry out these instructions, tasks like building a new copy of a cell, or repairing the damage.
Each type of protein is a specialist that only does one job, so if a cell needs to do something new, it must make a new protein to do this job. Similarly, if a cell needs to do something faster or slower than before, it makes more or less of the protein responsible. Genes tell cells what to do by telling them which proteins to make and in what amounts.
Proteins are made of a chain of 20 different types of amino acid molecules. This chain folds up into a compact shape, rather like an untidy ball of string. The shape of the protein is determined by the sequence of amino acids along its chain and it is this shape that, in turn, determines what the protein does.
For example, some proteins have parts of their surface that perfectly match the shape of another molecule, allowing the protein to bind to this molecule very tightly. Other proteins are enzymes, which are like tiny machines that alter other molecules.
The information in DNA is held in the sequence of the repeating units along the DNA chain. These units are four types of nucleotides (A,T,G and C) and the sequence of nucleotides stores information in an alphabet called the genetic code. When a gene is read by a cell the DNA sequence is copied into a very similar molecule called RNA (this process is called transcription).
Transcription is controlled by other DNA sequences (such as promoters), which show a cell where genes are, and control how often they are copied. The RNA copy made from a gene is then fed through a structure called a ribosome, which translates the sequence of nucleotides in the RNA into the correct sequence of amino acids and joins these amino acids together to make a complete protein chain.
The new protein then folds up into its active form. The process of moving information from the language of RNA into the language of amino acids is called translation.
If the sequence of the nucleotides in a gene changes, the sequence of the amino acids in the protein it produces may also change—if part of a gene is deleted, the protein produced is shorter and may not work anymore. This is the reason why different alleles of a gene can have different effects on an organism.
As an example, hair color depends on how much of a dark substance called melanin is put into the hair as it grows. If a person has a normal set of the genes involved in making melanin, they make all the proteins needed and they grow dark hair. However, if the alleles for a particular protein have different sequences and produce proteins that can't do their jobs, no melanin is produced and the person has white skin and hair (albinism).
Genes are copied:
Main article: DNA replication
Genes are copied each time a cell divides into two new cells. The process that copies DNA is called DNA replication. It is through a similar process that a child inherits genes from its parents when a copy from the mother is mixed with a copy from the father.
DNA can be copied very easily and accurately because each piece of DNA can direct the assembly of a new copy of its information. This is because DNA is made of two strands that pair together like the two sides of a zipper. The nucleotides are in the center, like the teeth in the zipper, and pair up to hold the two strands together.
Importantly, the four different sorts of nucleotides are different shapes, so for the strands to close up properly, an A nucleotide must go opposite a T nucleotide, and a G opposite a C. This exact pairing is called base pairing.
When DNA is copied, the two strands of the old DNA are pulled apart by enzymes; then they pair up with new nucleotides and then close. This produces two new pieces of DNA, each containing one strand from the old DNA and one newly made strand. This process is not predictably perfect as proteins attach to a nucleotide while they are building and cause a change in the sequence of that gene.
These changes in the DNA sequence are called mutations. Mutations produce new alleles of genes. Sometimes these changes stop the functioning of that gene or make it serve another advantageous function, such as the melanin genes discussed above. These mutations and their effects on the traits of organisms are one of the causes of evolution.
Genes and evolution
Further information:
A population of organisms evolves when an inherited trait becomes more common or less common over time. For instance, all the mice living on an island would be a single population of mice: some with white fur, some gray. If over generations, white mice became more frequent and gray mice less frequent, then the color of the fur in this population of mice would be evolving.
In terms of genetics, this is called an increase in allele frequency.
Alleles become more or less common either by chance in a process called genetic drift or by natural selection. In natural selection, if an allele makes it more likely for an organism to survive and reproduce, then over time this allele becomes more common. But if an allele is harmful, natural selection makes it less common.
In the above example, if the island were getting colder each year and snow became present for much of the time, then the allele for white fur would favor survival since predators would be less likely to see them against the snow, and more likely to see the gray mice. Over time white mice would become more and more frequent, while gray mice less and less.
Mutations create new alleles. These alleles have new DNA sequences and can produce proteins with new properties. So if an island was populated entirely by black mice, mutations could happen creating alleles for white fur.
The combination of mutations creating new alleles at random, and natural selection picking out those that are useful, causes an adaptation. This is when organisms change in ways that help them to survive and reproduce.
Many such changes, studied in evolutionary developmental biology, affect the way the embryo develops into an adult body.
Inherited diseases:
Some diseases are hereditary and run in families; others, such as infectious diseases, are caused by the environment. Other diseases come from a combination of genes and the environment.
Genetic disorders are diseases that are caused by a single allele of a gene and are inherited in families. These include:
Other diseases are influenced by genetics, but the genes a person gets from their parents only change their risk of getting a disease. Most of these diseases are inherited in a complex way, with either multiple genes involved, or coming from both genes and the environment.
As an example, the risk of breast cancer is 50 times higher in the families most at risk, compared to the families least at risk. This variation is probably due to a large number of alleles, each changing the risk a little bit. Several of the genes have been identified, such as BRCA1 and BRCA2, but not all of them.
However, although some of the risks are genetic, the risk of this cancer is also increased by being overweight, heavy alcohol consumption and not exercising. A woman's risk of breast cancer, therefore, comes from a large number of alleles interacting with her environment, so it is very hard to predict.
Genetic engineering: See Next Topic
See also:
Some traits are part of an organism's physical appearance, such as eye color or height. Other sorts of traits are not easily seen and include blood types or resistance to diseases.
Some traits are inherited through genes, which is the reason why tall and thin people tend to have tall and thin children. Other traits come from interactions between genes and the environment, so a child who inherited the tendency of being tall will still be short if poorly nourished. The way our genes and environment interact to produce a trait can be complicated. For example, the chances of somebody dying of cancer or heart disease seems to depend on both their genes and their lifestyle.
Genes are made from a long molecule called DNA, which is copied and inherited across generations. DNA is made of simple units that line up in a particular order within it, carrying genetic information. The language used by DNA is called genetic code, which lets organisms read the information in the genes. This information is the instructions for the construction and operation of a living organism.
The information within a particular gene is not always exactly the same between one organism and another, so different copies of a gene do not always give exactly the same instructions. Each unique form of a single gene is called an allele. As an example, one allele for the gene for hair color could instruct the body to produce much pigment, producing black hair, while a different allele of the same gene might give garbled instructions that fail to produce any pigment, giving white hair.
Mutations are random changes in genes and can create new alleles. Mutations can also produce new traits, such as when mutations to an allele for black hair produce a new allele for white hair. This appearance of new traits is important in evolution.
Genes and inheritance
Genes are pieces of DNA that contain information for the synthesis of ribonucleic acids (RNAs) or polypeptides. Genes are inherited as units, with two parents dividing out copies of their genes to their offspring.
Humans have two copies of each of their genes, but each egg or sperm cell only gets one of those copies for each gene. An egg and sperm join to form a zygote with a complete set of genes. The resulting offspring has the same number of genes as their parents, but for any gene, one of their two copies comes from their father and one from their mother.
Example of mixing:
The effects of mixing depend on the types (the alleles) of the gene. If the father has two copies of an allele for red hair, and the mother has two copies for brown hair, all their children get the two alleles that give different instructions, one for red hair and one for brown.
The hair color of these children depends on how these alleles work together. If one allele dominates the instructions from another, it is called the dominant allele, and the allele that is overridden is called the recessive allele. In the case of a daughter with alleles for both red and brown hair, brown is dominant and she ends up with brown hair.
Although the red color allele is still there in this brown-haired girl, it doesn't show. This is a difference between what is seen on the surface (the traits of an organism, called its phenotype) and the genes within the organism (its genotype).
In this example, the allele for brown can be called "B" and the allele for red "b". (It is normal to write dominant alleles with capital letters and recessive ones with lower-case letters.) The brown hair daughter has the "brown hair phenotype" but her genotype is Bb, with one copy of the B allele, and one of the b allele.
Now imagine that this woman grows up and has children with a brown-haired man who also has a Bb genotype. Her eggs will be a mixture of two types, one sort containing the B allele, and one sort the b allele.
Similarly, her partner will produce a mix of two types of sperm containing one or the other of these two alleles. When the transmitted genes are joined up in their offspring, these children have a chance of getting either brown or red hair, since they could get a genotype of BB = brown hair, Bb = brown hair or bb = red hair. In this generation, there is, therefore, a chance of the recessive allele showing itself in the phenotype of the children—some of them may have red hair like their grandfather.
Many traits are inherited in a more complicated way than the example above. This can happen when there are several genes involved, each contributing a small part to the result.
Tall people tend to have tall children because their children get a package of many alleles that each contribute a bit to how much they grow. However, there are not clear groups of "short people" and "tall people", like there are groups of people with brown or red hair.
This is because of the large number of genes involved; this makes the trait very variable and people are of many different heights. Despite a common misconception, the green/blue eye traits are also inherited in this complex inheritance model.
Inheritance can also be complicated when the trait depends on the interaction between genetics and environment. For example, malnutrition does not change traits like eye color, but can stunt growth.
How genes work:
Genes make proteins:
Main article: Genetic code
The function of genes is to provide the information needed to make molecules called proteins in cells. Cells are the smallest independent parts of organisms: the human body contains about 100 trillion cells, while very small organisms like bacteria are just a single cell.
A cell is like a miniature and very complex factory that can make all the parts needed to produce a copy of itself, which happens when cells divide. There is a simple division of labor in cells—genes give instructions and proteins carry out these instructions, tasks like building a new copy of a cell, or repairing the damage.
Each type of protein is a specialist that only does one job, so if a cell needs to do something new, it must make a new protein to do this job. Similarly, if a cell needs to do something faster or slower than before, it makes more or less of the protein responsible. Genes tell cells what to do by telling them which proteins to make and in what amounts.
Proteins are made of a chain of 20 different types of amino acid molecules. This chain folds up into a compact shape, rather like an untidy ball of string. The shape of the protein is determined by the sequence of amino acids along its chain and it is this shape that, in turn, determines what the protein does.
For example, some proteins have parts of their surface that perfectly match the shape of another molecule, allowing the protein to bind to this molecule very tightly. Other proteins are enzymes, which are like tiny machines that alter other molecules.
The information in DNA is held in the sequence of the repeating units along the DNA chain. These units are four types of nucleotides (A,T,G and C) and the sequence of nucleotides stores information in an alphabet called the genetic code. When a gene is read by a cell the DNA sequence is copied into a very similar molecule called RNA (this process is called transcription).
Transcription is controlled by other DNA sequences (such as promoters), which show a cell where genes are, and control how often they are copied. The RNA copy made from a gene is then fed through a structure called a ribosome, which translates the sequence of nucleotides in the RNA into the correct sequence of amino acids and joins these amino acids together to make a complete protein chain.
The new protein then folds up into its active form. The process of moving information from the language of RNA into the language of amino acids is called translation.
If the sequence of the nucleotides in a gene changes, the sequence of the amino acids in the protein it produces may also change—if part of a gene is deleted, the protein produced is shorter and may not work anymore. This is the reason why different alleles of a gene can have different effects on an organism.
As an example, hair color depends on how much of a dark substance called melanin is put into the hair as it grows. If a person has a normal set of the genes involved in making melanin, they make all the proteins needed and they grow dark hair. However, if the alleles for a particular protein have different sequences and produce proteins that can't do their jobs, no melanin is produced and the person has white skin and hair (albinism).
Genes are copied:
Main article: DNA replication
Genes are copied each time a cell divides into two new cells. The process that copies DNA is called DNA replication. It is through a similar process that a child inherits genes from its parents when a copy from the mother is mixed with a copy from the father.
DNA can be copied very easily and accurately because each piece of DNA can direct the assembly of a new copy of its information. This is because DNA is made of two strands that pair together like the two sides of a zipper. The nucleotides are in the center, like the teeth in the zipper, and pair up to hold the two strands together.
Importantly, the four different sorts of nucleotides are different shapes, so for the strands to close up properly, an A nucleotide must go opposite a T nucleotide, and a G opposite a C. This exact pairing is called base pairing.
When DNA is copied, the two strands of the old DNA are pulled apart by enzymes; then they pair up with new nucleotides and then close. This produces two new pieces of DNA, each containing one strand from the old DNA and one newly made strand. This process is not predictably perfect as proteins attach to a nucleotide while they are building and cause a change in the sequence of that gene.
These changes in the DNA sequence are called mutations. Mutations produce new alleles of genes. Sometimes these changes stop the functioning of that gene or make it serve another advantageous function, such as the melanin genes discussed above. These mutations and their effects on the traits of organisms are one of the causes of evolution.
Genes and evolution
Further information:
A population of organisms evolves when an inherited trait becomes more common or less common over time. For instance, all the mice living on an island would be a single population of mice: some with white fur, some gray. If over generations, white mice became more frequent and gray mice less frequent, then the color of the fur in this population of mice would be evolving.
In terms of genetics, this is called an increase in allele frequency.
Alleles become more or less common either by chance in a process called genetic drift or by natural selection. In natural selection, if an allele makes it more likely for an organism to survive and reproduce, then over time this allele becomes more common. But if an allele is harmful, natural selection makes it less common.
In the above example, if the island were getting colder each year and snow became present for much of the time, then the allele for white fur would favor survival since predators would be less likely to see them against the snow, and more likely to see the gray mice. Over time white mice would become more and more frequent, while gray mice less and less.
Mutations create new alleles. These alleles have new DNA sequences and can produce proteins with new properties. So if an island was populated entirely by black mice, mutations could happen creating alleles for white fur.
The combination of mutations creating new alleles at random, and natural selection picking out those that are useful, causes an adaptation. This is when organisms change in ways that help them to survive and reproduce.
Many such changes, studied in evolutionary developmental biology, affect the way the embryo develops into an adult body.
Inherited diseases:
Some diseases are hereditary and run in families; others, such as infectious diseases, are caused by the environment. Other diseases come from a combination of genes and the environment.
Genetic disorders are diseases that are caused by a single allele of a gene and are inherited in families. These include:
- Huntington's disease,
- cystic fibrosis or Duchenne muscular dystrophy.
- Cystic fibrosis, for example, is caused by mutations in a single gene called CFTR and is inherited as a recessive trait.
Other diseases are influenced by genetics, but the genes a person gets from their parents only change their risk of getting a disease. Most of these diseases are inherited in a complex way, with either multiple genes involved, or coming from both genes and the environment.
As an example, the risk of breast cancer is 50 times higher in the families most at risk, compared to the families least at risk. This variation is probably due to a large number of alleles, each changing the risk a little bit. Several of the genes have been identified, such as BRCA1 and BRCA2, but not all of them.
However, although some of the risks are genetic, the risk of this cancer is also increased by being overweight, heavy alcohol consumption and not exercising. A woman's risk of breast cancer, therefore, comes from a large number of alleles interacting with her environment, so it is very hard to predict.
Genetic engineering: See Next Topic
See also:
- Common misunderstandings of genetics
- Epigenetics
- Whole genome sequencing
- History of genetics
- Genetics in simple English
- Outline of genetics
- Molecular genetics
- Predictive medicine
- Introduction to Genetics, University of Utah
- Introduction to Genes and Disease, NCBI open book
- Genetics glossary, A talking glossary of genetic terms.
- Khan Academy on YouTube
- What Color Eyes Would Your Children Have? Genetics of human eye color: An interactive introduction
- Transcribe and translate a gene, University of Utah
Genetic Engineering
- YouTube Video: Genetic Engineering
- YouTube Video: The New World of Human Genetic Engineering
- YouTube Video: Changing the Blueprints of Life - Genetic Engineering
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms.
New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism.
The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
An organism that is generated through genetic engineering is considered to be genetically modified (GM) and the resulting entity is a genetically modified organism (GMO). The first GMO was a bacterium generated by Herbert Boyer and Stanley Cohen in 1973.
Rudolf Jaenisch created the first GM animal when he inserted foreign DNA into a mouse in 1974. The first company to focus on genetic engineering, Genentech, was founded in 1976 and started the production of human proteins.
Genetically engineered human insulin was produced in 1978 and insulin-producing bacteria were commercialised in 1982.
Genetically modified food has been sold since 1994, with the release of the Flavr Savr tomato. The Flavr Savr was engineered to have a longer shelf life, but most current GM crops are modified to increase resistance to insects and herbicides. GloFish, the first GMO designed as a pet, was sold in the United States in December 2003. In 2016 salmon modified with a growth hormone were sold.
Genetic engineering has been applied in numerous fields including research, medicine, industrial biotechnology and agriculture. In research, GMOs are used to study gene function and expression through loss of function, gain of function, tracking and expression experiments.
By knocking out genes responsible for certain conditions it is possible to create animal model organisms of human diseases. Besides producing hormones, vaccines and other drugs, genetic engineering has the potential to cure genetic diseases through gene therapy.
The same techniques that are used to produce drugs can also have industrial applications such as producing enzymes for laundry detergent, cheeses and other products.
The rise of commercialised genetically modified crops has provided economic benefit to farmers in many different countries, but has also been the source of most of the controversy surrounding the technology. This has been present since its early use; the first field trials were destroyed by anti-GM activists.
Although there is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, critics consider GM food safety a leading concern. Gene flow, impact on non-target organisms, control of the food supply and intellectual property rights have also been raised as potential issues.
These concerns have led to the development of a regulatory framework, which started in 1975. It has led to an international treaty, the Cartagena Protocol on Biosafety, that was adopted in 2000. Individual countries have developed their own regulatory systems regarding GMOs, with the most marked differences occurring between the US and Europe.
Overview:
Genetic engineering is a process that alters the genetic structure of an organism by either removing or introducing DNA, or modifying existing genetic material in situ. Unlike traditional animal and plant breeding, which involves doing multiple crosses and then selecting for the organism with the desired phenotype, genetic engineering takes the gene directly from one organism and delivers it to the other. This is much faster, can be used to insert any genes from any organism (even ones from different domains) and prevents other undesirable genes from also being added.
Genetic engineering could potentially fix severe genetic disorders in humans by replacing the defective gene with a functioning one. It is an important tool in research that allows the function of specific genes to be studied. Drugs, vaccines and other products have been harvested from organisms engineered to produce them. Crops have been developed that aid food security by increasing yield, nutritional value and tolerance to environmental stresses.
The DNA can be introduced directly into the host organism or into a cell that is then fused or hybridised with the host. This relies on recombinant nucleic acid techniques to form new combinations of heritable genetic material followed by the incorporation of that material either indirectly through a vector system or directly through micro-injection, macro-injection or micro-encapsulation.
Genetic engineering does not normally include traditional breeding, in vitro fertilisation, induction of polyploidy, mutagenesis and cell fusion techniques that do not use recombinant nucleic acids or a genetically modified organism in the process. However, some broad definitions of genetic engineering include selective breeding.
Cloning and stem cell research, although not considered genetic engineering, are closely related and genetic engineering can be used within them. Synthetic biology is an emerging discipline that takes genetic engineering a step further by introducing artificially synthesised material into an organism.
Plants, animals or microorganisms that have been changed through genetic engineering are termed genetically modified organisms or GMOs. If genetic material from another species is added to the host, the resulting organism is called transgenic. If genetic material from the same species or a species that can naturally breed with the host is used the resulting organism is called cisgenic.
If genetic engineering is used to remove genetic material from the target organism the resulting organism is termed a knockout organism. In Europe genetic modification is synonymous with genetic engineering while within the United States of America and Canada genetic modification can also be used to refer to more conventional breeding methods.
Process:
Main article: Genetic engineering techniques
Creating a GMO is a multi-step process. Genetic engineers must first choose what gene they wish to insert into the organism. This is driven by what the aim is for the resultant organism and is built on earlier research.
Genetic screens can be carried out to determine potential genes and further tests then used to identify the best candidates. The development of microarrays, transcriptomics and genome sequencing has made it much easier to find suitable genes. Luck also plays its part; the Roundup Ready gene was discovered after scientists noticed a bacterium thriving in the presence of the herbicide.
Gene isolation and cloning:
Main article: Molecular cloning
The next step is to isolate the candidate gene. The cell containing the gene is opened and the DNA is purified. The gene is separated by using restriction enzymes to cut the DNA into fragments or polymerase chain reaction (PCR) to amplify up the gene segment. These segments can then be extracted through gel electrophoresis:
Once isolated the gene is ligated into a plasmid that is then inserted into a bacterium. The plasmid is replicated when the bacteria divide, ensuring unlimited copies of the gene are available. The RK2 plasmid is notable for its ability to replicate in a wide variety of single-celled organisms, which makes it suitable as a genetic engineering tool.
Before the gene is inserted into the target organism it must be combined with other genetic elements. These include a promoter and terminator region, which initiate and end transcription. A selectable marker gene is added, which in most cases confers antibiotic resistance, so researchers can easily determine which cells have been successfully transformed. The gene can also be modified at this stage for better expression or effectiveness.
These manipulations are carried out using recombinant DNA techniques, such as restriction digests, ligations and molecular cloning.
Inserting DNA into the host genome:
Main article: Gene delivery
There are a number of techniques used to insert genetic material into the host genome. Some bacteria can naturally take up foreign DNA. This ability can be induced in other bacteria via stress (e.g. thermal or electric shock), which increases the cell membrane's permeability to DNA; up-taken DNA can either integrate with the genome or exist as extrachromosomal DNA.
DNA is generally inserted into animal cells using microinjection, where it can be injected through the cell's nuclear envelope directly into the nucleus, or through the use of viral vectors.
Plant genomes can be engineered by physical methods or by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. In plants the DNA is often inserted using Agrobacterium-mediated transformation, taking advantage of the Agrobacteriums T-DNA sequence that allows natural insertion of genetic material into plant cells.
Other methods include biolistics, where particles of gold or tungsten are coated with DNA and then shot into young plant cells, and electroporation, which involves using an electric shock to make the cell membrane permeable to plasmid DNA.
As only a single cell is transformed with genetic material, the organism must be regenerated from that single cell:
Bacteria consist of a single cell and reproduce clonally so regeneration is not necessary. Selectable markers are used to easily differentiate transformed from untransformed cells. These markers are usually present in the transgenic organism, although a number of strategies have been developed that can remove the selectable marker from the mature transgenic plant.
Further testing using PCR, Southern hybridization, and DNA sequencing is conducted to confirm that an organism contains the new gene. These tests can also confirm the chromosomal location and copy number of the inserted gene.
The presence of the gene does not guarantee it will be expressed at appropriate levels in the target tissue so methods that look for and measure the gene products (RNA and protein) are also used. These include:
The new genetic material can be inserted randomly within the host genome or targeted to a specific location. The technique of gene targeting uses homologous recombination to make desired changes to a specific endogenous gene. This tends to occur at a relatively low frequency in plants and animals and generally requires the use of selectable markers.
The frequency of gene targeting can be greatly enhanced through genome editing. Genome editing uses artificially engineered nucleases that create specific double-stranded breaks at desired locations in the genome, and use the cell's endogenous mechanisms to repair the induced break by the natural processes of homologous recombination and nonhomologous end-joining.
There are four families of engineered nucleases:
TALEN and CRISPR are the two most commonly used and each has its own advantages: TALENs have greater target specificity,
while CRISPR is easier to design and more efficient.
In addition to enhancing gene targeting, engineered nucleases can be used to introduce mutations at endogenous genes that generate a gene knockout.
Applications:
Genetic engineering has applications in medicine, research, industry and agriculture and can be used on a wide range of plants, animals and microorganisms. Bacteria, the first organisms to be genetically modified, can have plasmid DNA inserted containing new genes that code for medicines or enzymes that process food and other substrates.
Plants have been modified for:
Most commercialised GMOs are insect resistant or herbicide tolerant crop plants. Genetically modified animals have been used for research, model animals and the production of agricultural or pharmaceutical products. The genetically modified animals include animals with:
Medicine:
Genetic engineering has many applications to medicine that include the manufacturing of drugs, creation of model animals that mimic human conditions and gene therapy. One of the earliest uses of genetic engineering was to mass-produce human insulin in bacteria. This application has now been applied to:
Mouse hybridomas, cells fused together to create monoclonal antibodies, have been adapted through genetic engineering to create human monoclonal antibodies. Genetically engineered viruses are being developed that can still confer immunity, but lack the infectious sequences.
Genetic engineering is also used to create animal models of human diseases. Genetically modified mice are the most common genetically engineered animal model. They have been used to study and model:
Potential cures can be tested against these mouse models.
Gene therapy is the genetic engineering of humans, generally by replacing defective genes with effective ones. Clinical research using somatic gene therapy has been conducted with several diseases, including X-linked SCID, chronic lymphocytic leukemia (CLL), and Parkinson's disease.
In 2012, Alipogene tiparvovec became the first gene therapy treatment to be approved for clinical use. In 2015 a virus was used to insert a healthy gene into the skin cells of a boy suffering from a rare skin disease, epidermolysis bullosa, in order to grow, and then graft healthy skin onto 80 percent of the boy's body which was affected by the illness.
Germline gene therapy would result in any change being inheritable, which has raised concerns within the scientific community. In 2015, CRISPR was used to edit the DNA of non-viable human embryos, leading scientists of major world academies to call for a moratorium on inheritable human genome edits.
There are also concerns that the technology could be used not just for treatment, but for enhancement, modification or alteration of a human beings' appearance, adaptability, intelligence, character or behavior.
The distinction between cure and enhancement can also be difficult to establish. In November 2018, He Jiankui announced that he had edited the genomes of two human embryos, to attempt to disable the CCR5 gene, which codes for a receptor that HIV uses to enter cells. The work was widely condemned as unethical, dangerous, and premature.
Currently, germline modification is banned in 40 countries. Scientists that do this type of research will often let embryos grow for a few days without allowing it to develop into a baby.
Researchers are altering the genome of pigs to induce the growth of human organs, with the aim of increasing the success of pig to human organ transplantation. Scientists are creating "gene drives", changing the genomes of mosquitoes to make them immune to malaria, and then looking to spread the genetically altered mosquitoes throughout the mosquito population in the hopes of eliminating the disease.
Research:
Genetic engineering is an important tool for natural scientists, with the creation of transgenic organisms one of the most important tools for analysis of gene function. Genes and other genetic information from a wide range of organisms can be inserted into bacteria for storage and modification, creating genetically modified bacteria in the process.
Bacteria are cheap, easy to grow, clonal, multiply quickly, relatively easy to transform and can be stored at -80 °C almost indefinitely. Once a gene is isolated it can be stored inside the bacteria providing an unlimited supply for research.
Organisms are genetically engineered to discover the functions of certain genes. This could be the effect on the phenotype of the organism, where the gene is expressed or what other genes it interacts with. These experiments generally involve loss of function, gain of function, tracking and expression:
Loss of function experiments, such as in a gene knockout experiment, in which an organism is engineered to lack the activity of one or more genes. In a simple knockout a copy of the desired gene has been altered to make it non-functional. Embryonic stem cells incorporate the altered gene, which replaces the already present functional copy.
These stem cells are injected into blastocysts, which are implanted into surrogate mothers. This allows the experimenter to analyse the defects caused by this mutation and thereby determine the role of particular genes. It is used especially frequently in developmental biology.
When this is done by creating a library of genes with point mutations at every position in the area of interest, or even every position in the whole gene, this is called "scanning mutagenesis". The simplest method, and the first to be used, is "alanine scanning", where every position in turn is mutated to the unreactive amino acid alanine.
Gain of function experiments, the logical counterpart of knockouts. These are sometimes performed in conjunction with knockout experiments to more finely establish the function of the desired gene.
The process is much the same as that in knockout engineering, except that the construct is designed to increase the function of the gene, usually by providing extra copies of the gene or inducing synthesis of the protein more frequently.
Gain of function is used to tell whether or not a protein is sufficient for a function, but does not always mean it is required, especially when dealing with genetic or functional redundancy.
Tracking experiments, which seek to gain information about the localisation and interaction of the desired protein. One way to do this is to replace the wild-type gene with a 'fusion' gene, which is a juxtaposition of the wild-type gene with a reporting element such as green fluorescent protein (GFP) that will allow easy visualisation of the products of the genetic modification.
While this is a useful technique, the manipulation can destroy the function of the gene, creating secondary effects and possibly calling into question the results of the experiment.
More sophisticated techniques are now in development that can track protein products without mitigating their function, such as the addition of small sequences that will serve as binding motifs to monoclonal antibodies.
Expression studies aim to discover where and when specific proteins are produced. In these experiments, the DNA sequence before the DNA that codes for a protein, known as a gene's promoter, is reintroduced into an organism with the protein coding region replaced by a reporter gene such as GFP or an enzyme that catalyses the production of a dye.
Thus the time and place where a particular protein is produced can be observed. Expression studies can be taken a step further by altering the promoter to find which pieces are crucial for the proper expression of the gene and are actually bound by transcription factor proteins; this process is known as promoter bashing.
Industrial:
Main article: Industrial microbiology
Organisms can have their cells transformed with a gene coding for a useful protein, such as an enzyme, so that they will overexpress the desired protein. Mass quantities of the protein can then be manufactured by growing the transformed organism in bioreactor equipment using industrial fermentation, and then purifying the protein.
Some genes do not work well in bacteria, so yeast, insect cells or mammalian cells can also be used. These techniques are used to produce medicines such as:
Other applications with genetically engineered bacteria could involve making them perform tasks outside their natural cycle, such as:
Certain genetically modified microbes can also be used in biomining and bioremediation, due to their ability to extract heavy metals from their environment and incorporate them into compounds that are more easily recoverable.
In materials science, a genetically modified virus has been used in a research laboratory as a scaffold for assembling a more environmentally friendly lithium-ion battery. Bacteria have also been engineered to function as sensors by expressing a fluorescent protein under certain environmental conditions.
Agriculture:
Main articles:
One of the best-known and controversial applications of genetic engineering is the creation and use of genetically modified crops or genetically modified livestock to produce genetically modified food. Crops have been developed to increase production, increase tolerance to abiotic stresses, alter the composition of the food, or to produce novel products.
The first crops to be released commercially on a large scale provided protection from insect pests or tolerance to herbicides. Fungal and virus resistant crops have also been developed or are in development.
This makes the insect and weed management of crops easier and can indirectly increase crop yield. GM crops that directly improve yield by accelerating growth or making the plant more hardy (by improving salt, cold or drought tolerance) are also under development
In 2016 Salmon have been genetically modified with growth hormones to reach normal adult size much faster.
Genetically Modified Organisoms (GMO) have been developed that modify the quality of produce by increasing the nutritional value or providing more industrially useful qualities or quantities. The Amflora potato produces a more industrially useful blend of starches. Soybeans and canola have been genetically modified to produce more healthy oils. The first commercialised GM food was a tomato that had delayed ripening, increasing its shelf life.
Plants and animals have been engineered to produce materials they do not normally make. Pharming uses crops and animals as bioreactors to produce vaccines, drug intermediates, or the drugs themselves; the useful product is purified from the harvest and then used in the standard pharmaceutical production process. Cows and goats have been engineered to express drugs and other proteins in their milk, and in 2009 the FDA approved a drug produced in goat milk.
Other applications:
Genetic engineering has potential applications in conservation and natural area management. Gene transfer through viral vectors has been proposed as a means of controlling invasive species as well as vaccinating threatened fauna from disease. Transgenic trees have been suggested as a way to confer resistance to pathogens in wild populations.
With the increasing risks of maladaptation in organisms as a result of climate change and other perturbations, facilitated adaptation through gene tweaking could be one solution to reducing extinction risks. Applications of genetic engineering in conservation are thus far mostly theoretical and have yet to be put into practice.
Genetic engineering is also being used to create microbial art. Some bacteria have been genetically engineered to create black and white photographs. Novelty items such as lavender-colored carnations, blue roses, and glowing fish have also been produced through genetic engineering.
Regulation:
Main article: Regulation of genetic engineering
The regulation of genetic engineering concerns the approaches taken by governments to assess and manage the risks associated with the development and release of GMOs. The development of a regulatory framework began in 1975, at Asilomar, California.
The Asilomar meeting recommended a set of voluntary guidelines regarding the use of recombinant technology. As the technology improved the US established a committee at the Office of Science and Technology, which assigned regulatory approval of GM food to the USDA, FDA and EPA.
The Cartagena Protocol on Biosafety, an international treaty that governs the transfer, handling, and use of GMOs, was adopted on 29 January 2000. One hundred and fifty-seven countries are members of the Protocol, and many use it as a reference point for their own regulations.
The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation. Some countries allow the import of GM food with authorisation, but either do not allow its cultivation (Russia, Norway, Israel) or have provisions for cultivation even though no GM products are yet produced (Japan, South Korea).
Most countries that do not allow GMO cultivation do permit research. Some of the most marked differences occur between the US and Europe. The US policy focuses on the product (not the process), only looks at verifiable scientific risks and uses the concept of substantial equivalence. The European Union by contrast has possibly the most stringent GMO regulations in the world. All GMOs, along with irradiated food, are considered "new food" and subject to extensive, case-by-case, science-based food evaluation by the European Food Safety Authority.
The criteria for authorisation fall in four broad categories: "safety", "freedom of choice", "labelling", and "traceability". The level of regulation in other countries that cultivate GMOs lie in between Europe and the United States.
Click on image below for displaying the original links:
New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism.
The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
An organism that is generated through genetic engineering is considered to be genetically modified (GM) and the resulting entity is a genetically modified organism (GMO). The first GMO was a bacterium generated by Herbert Boyer and Stanley Cohen in 1973.
Rudolf Jaenisch created the first GM animal when he inserted foreign DNA into a mouse in 1974. The first company to focus on genetic engineering, Genentech, was founded in 1976 and started the production of human proteins.
Genetically engineered human insulin was produced in 1978 and insulin-producing bacteria were commercialised in 1982.
Genetically modified food has been sold since 1994, with the release of the Flavr Savr tomato. The Flavr Savr was engineered to have a longer shelf life, but most current GM crops are modified to increase resistance to insects and herbicides. GloFish, the first GMO designed as a pet, was sold in the United States in December 2003. In 2016 salmon modified with a growth hormone were sold.
Genetic engineering has been applied in numerous fields including research, medicine, industrial biotechnology and agriculture. In research, GMOs are used to study gene function and expression through loss of function, gain of function, tracking and expression experiments.
By knocking out genes responsible for certain conditions it is possible to create animal model organisms of human diseases. Besides producing hormones, vaccines and other drugs, genetic engineering has the potential to cure genetic diseases through gene therapy.
The same techniques that are used to produce drugs can also have industrial applications such as producing enzymes for laundry detergent, cheeses and other products.
The rise of commercialised genetically modified crops has provided economic benefit to farmers in many different countries, but has also been the source of most of the controversy surrounding the technology. This has been present since its early use; the first field trials were destroyed by anti-GM activists.
Although there is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, critics consider GM food safety a leading concern. Gene flow, impact on non-target organisms, control of the food supply and intellectual property rights have also been raised as potential issues.
These concerns have led to the development of a regulatory framework, which started in 1975. It has led to an international treaty, the Cartagena Protocol on Biosafety, that was adopted in 2000. Individual countries have developed their own regulatory systems regarding GMOs, with the most marked differences occurring between the US and Europe.
Overview:
Genetic engineering is a process that alters the genetic structure of an organism by either removing or introducing DNA, or modifying existing genetic material in situ. Unlike traditional animal and plant breeding, which involves doing multiple crosses and then selecting for the organism with the desired phenotype, genetic engineering takes the gene directly from one organism and delivers it to the other. This is much faster, can be used to insert any genes from any organism (even ones from different domains) and prevents other undesirable genes from also being added.
Genetic engineering could potentially fix severe genetic disorders in humans by replacing the defective gene with a functioning one. It is an important tool in research that allows the function of specific genes to be studied. Drugs, vaccines and other products have been harvested from organisms engineered to produce them. Crops have been developed that aid food security by increasing yield, nutritional value and tolerance to environmental stresses.
The DNA can be introduced directly into the host organism or into a cell that is then fused or hybridised with the host. This relies on recombinant nucleic acid techniques to form new combinations of heritable genetic material followed by the incorporation of that material either indirectly through a vector system or directly through micro-injection, macro-injection or micro-encapsulation.
Genetic engineering does not normally include traditional breeding, in vitro fertilisation, induction of polyploidy, mutagenesis and cell fusion techniques that do not use recombinant nucleic acids or a genetically modified organism in the process. However, some broad definitions of genetic engineering include selective breeding.
Cloning and stem cell research, although not considered genetic engineering, are closely related and genetic engineering can be used within them. Synthetic biology is an emerging discipline that takes genetic engineering a step further by introducing artificially synthesised material into an organism.
Plants, animals or microorganisms that have been changed through genetic engineering are termed genetically modified organisms or GMOs. If genetic material from another species is added to the host, the resulting organism is called transgenic. If genetic material from the same species or a species that can naturally breed with the host is used the resulting organism is called cisgenic.
If genetic engineering is used to remove genetic material from the target organism the resulting organism is termed a knockout organism. In Europe genetic modification is synonymous with genetic engineering while within the United States of America and Canada genetic modification can also be used to refer to more conventional breeding methods.
Process:
Main article: Genetic engineering techniques
Creating a GMO is a multi-step process. Genetic engineers must first choose what gene they wish to insert into the organism. This is driven by what the aim is for the resultant organism and is built on earlier research.
Genetic screens can be carried out to determine potential genes and further tests then used to identify the best candidates. The development of microarrays, transcriptomics and genome sequencing has made it much easier to find suitable genes. Luck also plays its part; the Roundup Ready gene was discovered after scientists noticed a bacterium thriving in the presence of the herbicide.
Gene isolation and cloning:
Main article: Molecular cloning
The next step is to isolate the candidate gene. The cell containing the gene is opened and the DNA is purified. The gene is separated by using restriction enzymes to cut the DNA into fragments or polymerase chain reaction (PCR) to amplify up the gene segment. These segments can then be extracted through gel electrophoresis:
- If the chosen gene or the donor organism's genome has been well studied it may already be accessible from a genetic library.
- If the DNA sequence is known, but no copies of the gene are available, it can also be artificially synthesised.
Once isolated the gene is ligated into a plasmid that is then inserted into a bacterium. The plasmid is replicated when the bacteria divide, ensuring unlimited copies of the gene are available. The RK2 plasmid is notable for its ability to replicate in a wide variety of single-celled organisms, which makes it suitable as a genetic engineering tool.
Before the gene is inserted into the target organism it must be combined with other genetic elements. These include a promoter and terminator region, which initiate and end transcription. A selectable marker gene is added, which in most cases confers antibiotic resistance, so researchers can easily determine which cells have been successfully transformed. The gene can also be modified at this stage for better expression or effectiveness.
These manipulations are carried out using recombinant DNA techniques, such as restriction digests, ligations and molecular cloning.
Inserting DNA into the host genome:
Main article: Gene delivery
There are a number of techniques used to insert genetic material into the host genome. Some bacteria can naturally take up foreign DNA. This ability can be induced in other bacteria via stress (e.g. thermal or electric shock), which increases the cell membrane's permeability to DNA; up-taken DNA can either integrate with the genome or exist as extrachromosomal DNA.
DNA is generally inserted into animal cells using microinjection, where it can be injected through the cell's nuclear envelope directly into the nucleus, or through the use of viral vectors.
Plant genomes can be engineered by physical methods or by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. In plants the DNA is often inserted using Agrobacterium-mediated transformation, taking advantage of the Agrobacteriums T-DNA sequence that allows natural insertion of genetic material into plant cells.
Other methods include biolistics, where particles of gold or tungsten are coated with DNA and then shot into young plant cells, and electroporation, which involves using an electric shock to make the cell membrane permeable to plasmid DNA.
As only a single cell is transformed with genetic material, the organism must be regenerated from that single cell:
- In plants this is accomplished through the use of tissue culture.
- In animals it is necessary to ensure that the inserted DNA is present in the embryonic stem cells.
Bacteria consist of a single cell and reproduce clonally so regeneration is not necessary. Selectable markers are used to easily differentiate transformed from untransformed cells. These markers are usually present in the transgenic organism, although a number of strategies have been developed that can remove the selectable marker from the mature transgenic plant.
Further testing using PCR, Southern hybridization, and DNA sequencing is conducted to confirm that an organism contains the new gene. These tests can also confirm the chromosomal location and copy number of the inserted gene.
The presence of the gene does not guarantee it will be expressed at appropriate levels in the target tissue so methods that look for and measure the gene products (RNA and protein) are also used. These include:
- northern hybridisation,
- quantitative RT-PCR,
- Western blot,
- immunofluorescence,
- ELISA
- and phenotypic analysis.
The new genetic material can be inserted randomly within the host genome or targeted to a specific location. The technique of gene targeting uses homologous recombination to make desired changes to a specific endogenous gene. This tends to occur at a relatively low frequency in plants and animals and generally requires the use of selectable markers.
The frequency of gene targeting can be greatly enhanced through genome editing. Genome editing uses artificially engineered nucleases that create specific double-stranded breaks at desired locations in the genome, and use the cell's endogenous mechanisms to repair the induced break by the natural processes of homologous recombination and nonhomologous end-joining.
There are four families of engineered nucleases:
- meganucleases,
- zinc finger nucleases,
- transcription activator-like effector nucleases (TALENs),
- and the Cas9-guideRNA system (adapted from CRISPR).
TALEN and CRISPR are the two most commonly used and each has its own advantages: TALENs have greater target specificity,
while CRISPR is easier to design and more efficient.
In addition to enhancing gene targeting, engineered nucleases can be used to introduce mutations at endogenous genes that generate a gene knockout.
Applications:
Genetic engineering has applications in medicine, research, industry and agriculture and can be used on a wide range of plants, animals and microorganisms. Bacteria, the first organisms to be genetically modified, can have plasmid DNA inserted containing new genes that code for medicines or enzymes that process food and other substrates.
Plants have been modified for:
- insect protection,
- herbicide resistance,
- virus resistance,
- enhanced nutrition,
- tolerance to environmental pressures
- and the production of edible vaccines.
Most commercialised GMOs are insect resistant or herbicide tolerant crop plants. Genetically modified animals have been used for research, model animals and the production of agricultural or pharmaceutical products. The genetically modified animals include animals with:
- genes knocked out,
- increased susceptibility to disease,
- hormones for extra growth
- and the ability to express proteins in their milk.
Medicine:
Genetic engineering has many applications to medicine that include the manufacturing of drugs, creation of model animals that mimic human conditions and gene therapy. One of the earliest uses of genetic engineering was to mass-produce human insulin in bacteria. This application has now been applied to:
- human growth hormones,
- follicle stimulating hormones (for treating infertility),
- human albumin,
- monoclonal antibodies,
- antihemophilic factors,
- vaccines
- and many other drugs.
Mouse hybridomas, cells fused together to create monoclonal antibodies, have been adapted through genetic engineering to create human monoclonal antibodies. Genetically engineered viruses are being developed that can still confer immunity, but lack the infectious sequences.
Genetic engineering is also used to create animal models of human diseases. Genetically modified mice are the most common genetically engineered animal model. They have been used to study and model:
- cancer (the oncomouse),
- obesity,
- heart disease,
- diabetes,
- arthritis,
- substance abuse,
- anxiety,
- aging
- and Parkinson disease.
Potential cures can be tested against these mouse models.
Gene therapy is the genetic engineering of humans, generally by replacing defective genes with effective ones. Clinical research using somatic gene therapy has been conducted with several diseases, including X-linked SCID, chronic lymphocytic leukemia (CLL), and Parkinson's disease.
In 2012, Alipogene tiparvovec became the first gene therapy treatment to be approved for clinical use. In 2015 a virus was used to insert a healthy gene into the skin cells of a boy suffering from a rare skin disease, epidermolysis bullosa, in order to grow, and then graft healthy skin onto 80 percent of the boy's body which was affected by the illness.
Germline gene therapy would result in any change being inheritable, which has raised concerns within the scientific community. In 2015, CRISPR was used to edit the DNA of non-viable human embryos, leading scientists of major world academies to call for a moratorium on inheritable human genome edits.
There are also concerns that the technology could be used not just for treatment, but for enhancement, modification or alteration of a human beings' appearance, adaptability, intelligence, character or behavior.
The distinction between cure and enhancement can also be difficult to establish. In November 2018, He Jiankui announced that he had edited the genomes of two human embryos, to attempt to disable the CCR5 gene, which codes for a receptor that HIV uses to enter cells. The work was widely condemned as unethical, dangerous, and premature.
Currently, germline modification is banned in 40 countries. Scientists that do this type of research will often let embryos grow for a few days without allowing it to develop into a baby.
Researchers are altering the genome of pigs to induce the growth of human organs, with the aim of increasing the success of pig to human organ transplantation. Scientists are creating "gene drives", changing the genomes of mosquitoes to make them immune to malaria, and then looking to spread the genetically altered mosquitoes throughout the mosquito population in the hopes of eliminating the disease.
Research:
Genetic engineering is an important tool for natural scientists, with the creation of transgenic organisms one of the most important tools for analysis of gene function. Genes and other genetic information from a wide range of organisms can be inserted into bacteria for storage and modification, creating genetically modified bacteria in the process.
Bacteria are cheap, easy to grow, clonal, multiply quickly, relatively easy to transform and can be stored at -80 °C almost indefinitely. Once a gene is isolated it can be stored inside the bacteria providing an unlimited supply for research.
Organisms are genetically engineered to discover the functions of certain genes. This could be the effect on the phenotype of the organism, where the gene is expressed or what other genes it interacts with. These experiments generally involve loss of function, gain of function, tracking and expression:
Loss of function experiments, such as in a gene knockout experiment, in which an organism is engineered to lack the activity of one or more genes. In a simple knockout a copy of the desired gene has been altered to make it non-functional. Embryonic stem cells incorporate the altered gene, which replaces the already present functional copy.
These stem cells are injected into blastocysts, which are implanted into surrogate mothers. This allows the experimenter to analyse the defects caused by this mutation and thereby determine the role of particular genes. It is used especially frequently in developmental biology.
When this is done by creating a library of genes with point mutations at every position in the area of interest, or even every position in the whole gene, this is called "scanning mutagenesis". The simplest method, and the first to be used, is "alanine scanning", where every position in turn is mutated to the unreactive amino acid alanine.
Gain of function experiments, the logical counterpart of knockouts. These are sometimes performed in conjunction with knockout experiments to more finely establish the function of the desired gene.
The process is much the same as that in knockout engineering, except that the construct is designed to increase the function of the gene, usually by providing extra copies of the gene or inducing synthesis of the protein more frequently.
Gain of function is used to tell whether or not a protein is sufficient for a function, but does not always mean it is required, especially when dealing with genetic or functional redundancy.
Tracking experiments, which seek to gain information about the localisation and interaction of the desired protein. One way to do this is to replace the wild-type gene with a 'fusion' gene, which is a juxtaposition of the wild-type gene with a reporting element such as green fluorescent protein (GFP) that will allow easy visualisation of the products of the genetic modification.
While this is a useful technique, the manipulation can destroy the function of the gene, creating secondary effects and possibly calling into question the results of the experiment.
More sophisticated techniques are now in development that can track protein products without mitigating their function, such as the addition of small sequences that will serve as binding motifs to monoclonal antibodies.
Expression studies aim to discover where and when specific proteins are produced. In these experiments, the DNA sequence before the DNA that codes for a protein, known as a gene's promoter, is reintroduced into an organism with the protein coding region replaced by a reporter gene such as GFP or an enzyme that catalyses the production of a dye.
Thus the time and place where a particular protein is produced can be observed. Expression studies can be taken a step further by altering the promoter to find which pieces are crucial for the proper expression of the gene and are actually bound by transcription factor proteins; this process is known as promoter bashing.
Industrial:
Main article: Industrial microbiology
Organisms can have their cells transformed with a gene coding for a useful protein, such as an enzyme, so that they will overexpress the desired protein. Mass quantities of the protein can then be manufactured by growing the transformed organism in bioreactor equipment using industrial fermentation, and then purifying the protein.
Some genes do not work well in bacteria, so yeast, insect cells or mammalian cells can also be used. These techniques are used to produce medicines such as:
- insulin,
- human growth hormone,
- and vaccines,
- supplements such as tryptophan, aid in the production of food (chymosin in cheese making)
- and fuels.
Other applications with genetically engineered bacteria could involve making them perform tasks outside their natural cycle, such as:
- making biofuels,
- cleaning up oil spills, carbon and other toxic waste
- and detecting arsenic in drinking water.
Certain genetically modified microbes can also be used in biomining and bioremediation, due to their ability to extract heavy metals from their environment and incorporate them into compounds that are more easily recoverable.
In materials science, a genetically modified virus has been used in a research laboratory as a scaffold for assembling a more environmentally friendly lithium-ion battery. Bacteria have also been engineered to function as sensors by expressing a fluorescent protein under certain environmental conditions.
Agriculture:
Main articles:
One of the best-known and controversial applications of genetic engineering is the creation and use of genetically modified crops or genetically modified livestock to produce genetically modified food. Crops have been developed to increase production, increase tolerance to abiotic stresses, alter the composition of the food, or to produce novel products.
The first crops to be released commercially on a large scale provided protection from insect pests or tolerance to herbicides. Fungal and virus resistant crops have also been developed or are in development.
This makes the insect and weed management of crops easier and can indirectly increase crop yield. GM crops that directly improve yield by accelerating growth or making the plant more hardy (by improving salt, cold or drought tolerance) are also under development
In 2016 Salmon have been genetically modified with growth hormones to reach normal adult size much faster.
Genetically Modified Organisoms (GMO) have been developed that modify the quality of produce by increasing the nutritional value or providing more industrially useful qualities or quantities. The Amflora potato produces a more industrially useful blend of starches. Soybeans and canola have been genetically modified to produce more healthy oils. The first commercialised GM food was a tomato that had delayed ripening, increasing its shelf life.
Plants and animals have been engineered to produce materials they do not normally make. Pharming uses crops and animals as bioreactors to produce vaccines, drug intermediates, or the drugs themselves; the useful product is purified from the harvest and then used in the standard pharmaceutical production process. Cows and goats have been engineered to express drugs and other proteins in their milk, and in 2009 the FDA approved a drug produced in goat milk.
Other applications:
Genetic engineering has potential applications in conservation and natural area management. Gene transfer through viral vectors has been proposed as a means of controlling invasive species as well as vaccinating threatened fauna from disease. Transgenic trees have been suggested as a way to confer resistance to pathogens in wild populations.
With the increasing risks of maladaptation in organisms as a result of climate change and other perturbations, facilitated adaptation through gene tweaking could be one solution to reducing extinction risks. Applications of genetic engineering in conservation are thus far mostly theoretical and have yet to be put into practice.
Genetic engineering is also being used to create microbial art. Some bacteria have been genetically engineered to create black and white photographs. Novelty items such as lavender-colored carnations, blue roses, and glowing fish have also been produced through genetic engineering.
Regulation:
Main article: Regulation of genetic engineering
The regulation of genetic engineering concerns the approaches taken by governments to assess and manage the risks associated with the development and release of GMOs. The development of a regulatory framework began in 1975, at Asilomar, California.
The Asilomar meeting recommended a set of voluntary guidelines regarding the use of recombinant technology. As the technology improved the US established a committee at the Office of Science and Technology, which assigned regulatory approval of GM food to the USDA, FDA and EPA.
The Cartagena Protocol on Biosafety, an international treaty that governs the transfer, handling, and use of GMOs, was adopted on 29 January 2000. One hundred and fifty-seven countries are members of the Protocol, and many use it as a reference point for their own regulations.
The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation. Some countries allow the import of GM food with authorisation, but either do not allow its cultivation (Russia, Norway, Israel) or have provisions for cultivation even though no GM products are yet produced (Japan, South Korea).
Most countries that do not allow GMO cultivation do permit research. Some of the most marked differences occur between the US and Europe. The US policy focuses on the product (not the process), only looks at verifiable scientific risks and uses the concept of substantial equivalence. The European Union by contrast has possibly the most stringent GMO regulations in the world. All GMOs, along with irradiated food, are considered "new food" and subject to extensive, case-by-case, science-based food evaluation by the European Food Safety Authority.
The criteria for authorisation fall in four broad categories: "safety", "freedom of choice", "labelling", and "traceability". The level of regulation in other countries that cultivate GMOs lie in between Europe and the United States.
Click on image below for displaying the original links:
One of the key issues concerning regulators is whether GM products should be labeled. The European Commission says that mandatory labeling and traceability are needed to allow for informed choice, avoid potential false advertising and facilitate the withdrawal of products if adverse effects on health or the environment are discovered.
The American Medical Association and the American Association for the Advancement of Science say that absent scientific evidence of harm even voluntary labeling is misleading and will falsely alarm consumers.
Labeling of GMO products in the marketplace is required in 64 countries. Labeling can be mandatory up to a threshold GM content level (which varies between countries) or voluntary.
In Canada and the US labeling of GM food is voluntary, while in Europe all food (including processed food) or feed which contains greater than 0.9% of approved GMOs must be labelled.
Controversy:
Main article: Genetically modified food controversies
Critics have objected to the use of genetic engineering on several grounds, including ethical, ecological and economic concerns. Many of these concerns involve GM crops and whether food produced from them is safe and what impact growing them will have on the environment.
These controversies have led to litigation, international trade disputes, and protests, and to restrictive regulation of commercial products in some countries.
Accusations that scientists are "playing God" and other religious issues have been ascribed to the technology from the beginning. Other ethical issues raised include the patenting of life, the use of intellectual property rights, the level of labeling on products, control of the food supply and the objectivity of the regulatory process.
Although doubts have been raised, economically most studies have found growing GM crops to be beneficial to farmers.
Gene flow between GM crops and compatible plants, along with increased use of selective herbicides, can increase the risk of "superweeds" developing. Other environmental concerns involve potential impacts on non-target organisms, including soil microbes, and an increase in secondary and resistant insect pests.
Many of the environmental impacts regarding GM crops may take many years to be understood and are also evident in conventional agriculture practices. With the commercialisation of genetically modified fish there are concerns over what the environmental consequences will be if they escape.
There are three main concerns over the safety of genetically modified food: whether they may provoke an allergic reaction; whether the genes could transfer from the food into human cells; and whether the genes not approved for human consumption could outcross to other crops.
There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. Nonetheless, members of the public are less likely than scientists to perceive GM foods as safe.
In popular culture:
Main article: Genetics in fiction § Genetic engineering
Genetic engineering features in many science fiction stories. Frank Herbert's novel The White Plague describes the deliberate use of genetic engineering to create a pathogen which specifically kills women. Another of Herbert's creations, the Dune series of novels, uses genetic engineering to create the powerful Tleilaxu.
Few films have informed audiences about genetic engineering, with the exception of the 1978 The Boys from Brazil and the 1993 Jurassic Park, both of which make use of a lesson, a demonstration, and a clip of scientific film.
Genetic engineering methods are weakly represented in film; Michael Clark, writing for the Wellcome Trust, calls the portrayal of genetic engineering and biotechnology "seriously distorted" in films such as The 6th Day. In Clark's view, the biotechnology is typically "given fantastic but visually arresting forms" while the science is either relegated to the background or fictionalised to suit a young audience.
In the 2007 video game, BioShock, genetic engineering plays an important role in the central storyline and universe. The game takes place in the fictional underwater dystopia Rapture, in which its inhabitants possess genetic superhuman abilities after injecting themselves with "plasmids", a serum which grants such powers.
Also in the city of Rapture are "Little Sisters", little girls who are generically engineered, as well as a side-plot in which a cabaret singer sells her foetus to genetic scientists who implant false memories into the newborn and genetically engineer it to grow into an adult.
See also:
The American Medical Association and the American Association for the Advancement of Science say that absent scientific evidence of harm even voluntary labeling is misleading and will falsely alarm consumers.
Labeling of GMO products in the marketplace is required in 64 countries. Labeling can be mandatory up to a threshold GM content level (which varies between countries) or voluntary.
In Canada and the US labeling of GM food is voluntary, while in Europe all food (including processed food) or feed which contains greater than 0.9% of approved GMOs must be labelled.
Controversy:
Main article: Genetically modified food controversies
Critics have objected to the use of genetic engineering on several grounds, including ethical, ecological and economic concerns. Many of these concerns involve GM crops and whether food produced from them is safe and what impact growing them will have on the environment.
These controversies have led to litigation, international trade disputes, and protests, and to restrictive regulation of commercial products in some countries.
Accusations that scientists are "playing God" and other religious issues have been ascribed to the technology from the beginning. Other ethical issues raised include the patenting of life, the use of intellectual property rights, the level of labeling on products, control of the food supply and the objectivity of the regulatory process.
Although doubts have been raised, economically most studies have found growing GM crops to be beneficial to farmers.
Gene flow between GM crops and compatible plants, along with increased use of selective herbicides, can increase the risk of "superweeds" developing. Other environmental concerns involve potential impacts on non-target organisms, including soil microbes, and an increase in secondary and resistant insect pests.
Many of the environmental impacts regarding GM crops may take many years to be understood and are also evident in conventional agriculture practices. With the commercialisation of genetically modified fish there are concerns over what the environmental consequences will be if they escape.
There are three main concerns over the safety of genetically modified food: whether they may provoke an allergic reaction; whether the genes could transfer from the food into human cells; and whether the genes not approved for human consumption could outcross to other crops.
There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. Nonetheless, members of the public are less likely than scientists to perceive GM foods as safe.
In popular culture:
Main article: Genetics in fiction § Genetic engineering
Genetic engineering features in many science fiction stories. Frank Herbert's novel The White Plague describes the deliberate use of genetic engineering to create a pathogen which specifically kills women. Another of Herbert's creations, the Dune series of novels, uses genetic engineering to create the powerful Tleilaxu.
Few films have informed audiences about genetic engineering, with the exception of the 1978 The Boys from Brazil and the 1993 Jurassic Park, both of which make use of a lesson, a demonstration, and a clip of scientific film.
Genetic engineering methods are weakly represented in film; Michael Clark, writing for the Wellcome Trust, calls the portrayal of genetic engineering and biotechnology "seriously distorted" in films such as The 6th Day. In Clark's view, the biotechnology is typically "given fantastic but visually arresting forms" while the science is either relegated to the background or fictionalised to suit a young audience.
In the 2007 video game, BioShock, genetic engineering plays an important role in the central storyline and universe. The game takes place in the fictional underwater dystopia Rapture, in which its inhabitants possess genetic superhuman abilities after injecting themselves with "plasmids", a serum which grants such powers.
Also in the city of Rapture are "Little Sisters", little girls who are generically engineered, as well as a side-plot in which a cabaret singer sells her foetus to genetic scientists who implant false memories into the newborn and genetically engineer it to grow into an adult.
See also:
- Biological engineering
- Modifications (genetics)
- RNA editing#Therapeutic mRNA Editing
- Semi-synthetic organisms
- Mutagenesis (molecular biology technique)
Albert Einstein
- YouTube Video: What Were Einstein's Greatest Achievements? (Happy 135th Birthday Albert Einstein!)
- YouTube Video: Albert Einstein: Father of modern physics
- YouTube Video: Lean all about Einsteins life and his major discoveries
* - Open Immersive Reader E=mc2:
The Story Behind Einstein's Immortal Equation
It has been more than a century ago that Albert Einstein arrived at his immortal equation E=mc2. It can rightly be said that a new age in modern physics started with Albert Einstein whose legacy will stay with us for a long time to come. The equation that bears his name is as famous as Einstein himself.
Indeed, the equation has been immortalized by its utter simplicity and its profound meaning and impact in our civilization. The energy E of a body (at rest) is equal to its mass 'm' multiplied by c2 (that is c x c), where 'c' equals the speed of light (in vacuum). The equation’s message is that the mass and energy of a body are convertible, and the mass of a body measures its energy content.
We can do some simple computation by using the SI system where m = mass in kg, c = speed of light 300,000,000 (approx) (that is 3 x 108) meter per sec, and E = the energy in Joules (3.6 million Joules equals one kilowatt-hour, kWh). Taking 'm' as 1 kg, we can calculate the energy content of 1 kg of matter (any matter) as E= mc2 =1 x c2 = 1 x (3 x 108) 2 = 9x1016 Joules = 25 x10 9 kWh, that is 25.0 billion kilowatt-hours
How much energy is that? If we consider 10,000 kWh to be the average annual power consumption (833 kWh per month) of a modern household, this one kg equivalent energy will give enough energy for 2,500,000 years that is 2.5 million years.
The equation E=mc2 becomes more fundamental if we consider the unit of c, the speed of light, as 'one light year per year' in which case c2 converts to I, and the equation becomes just E=m, meaning energy and mass are equal and the same. This is the most simple, fundamental and most profound equation ever evolved by humanity.
When the full meaning of the equation was known by the general public with the equivalence of mass and energy, someone asked Einstein, how come this fact was not known to us before?
The answer given by Einstein was very simple but at the same time very profound. He said, consider a rich man who has not spent a single penny all his life. How you would know that he is rich? In case of matter, the situation is like that. We never knew that matter possesses so much energy.
His answer reads like a Buddhist Jataka story of 'Hidden Treasure' where the poor monk had an invaluable gem sewn in his garment all his life which he did not know.
Einstein formulated this equation in 1905.
The question is how Einstein has arrived at this equation? How and why others could not? Many would think that being a mathematical genius, Einstein, might have evolved the equation after intense mathematical analysis. In fact nothing is further from the truth. As a matter of fact, Einstein was neither the first person to consider the equivalence of mass and energy, nor did he actually prove it. He just proposed the equation.
In order to understand how he evolved the equation, and how and why he received all the credit and fame for E=mc2, we will have understand a bit of history of science of his time as well as a bit of the life of Albert Einstein.
Albert Einstein was born in 1879 in Germany of a Jewish family, and as a child he grew up in the city of Munich. When Albert was a child, he had a remarkable experience of his first 'wonder' of nature. When little Albert was just five years old, his father gave him a pocket compass. The compass with its needle moving in a determined way by an unknown force, made a lasting and profound impression on the future theoretical physicist. This was one of the things that drove him to study science.
When he was twelve, he experienced his second joy and 'wonder' of a different kind when somebody gave him a little book dealing with Euclidian plane geometry. The theorems like "The theorems like 'three altitudes of a triangle are concurrent', the Pythagoras theorem and others gave him so much joy and wonder, that he remembered this all his life and wrote about it in his autobiographical notes years later.
As an youth, Einstein was a discontented and an independent thinker. At home he was stimulated more by a free exchange of ideas with his liberal parents. At sixteen, he told his father that he no longer wished to be German and at the same time announced that while he loved the Jewish culture, he was severing all formal connections with the Jewish faith.
His independent readings included many and was especially thrilled with natural sciences, geometry, philosophy (Spinoza, Buddhism etc), history, music and all. He was also playing the Violin. He was inquisitive and interested to know everything. However, at the advice of his father, he decided to focus on something which will assure him a job - especially important for a Jewish boy.
Otherwise, according to his own admission, he might have ended up being a musician.
However, he was also good in science. While studying in high school, Einstein familiarized himself with the elements of mathematics. By the time he was seventeen and ready to go to college, he also studied quite a bit of college physics. A number of scientific theories and mathematical equations had been worked out by the physicists at that time.
There were however a few situations where these theories couldn't satisfactorily explain. Einstein was interested to study these riddles on his own and to offer explanations.
When there were no riddles, he used to create his own riddle. When he was sixteen (1895), one such riddle that he created for himself was this: He used to imagine what would happen if he would fly with a beam of light. If he would move at the same speed of light, would he see the light waves as frozen? Would he see himself in a mirror if he would carry a mirror with him?
That was a riddle none of the physicists were interested to bother. They had too many other important issues to bother. But Einstein was not a professional physicist, he was just a college student studying physics and mathematics. For Einstein, the riddle was very intriguing, and he became passionately inquisitive about it. During these ten years, there was probably not a single day when he was not thinking about the problem and probably not a single night when he was not going to bed with the problem in his head.
The problem remained in his conscious and subconscious mind everyday of his life till he could solve the riddle in 1905.
During these ten years, he graduated from the Polytechnic in 1900 with a diploma to teach to math and physics. However, he could not find any job and he remained unemployed for quite some time.
Finally, he could land up a job as a clerk in the Patent office. This however become a blessing in disguise for Einstein. Working in the Patent office required less demands of his time. He soon discovered that he could go back to his 'Gedanken experiments,' or 'thought experiments' (meditations) that had tantalized him so far to concentrate on solving such scientific riddles.
During this time he also met a girl named Mileva, a class mate, with whom he fell in love and they got married.
Einstein had studied Maxwell's equations of electromagnetic waves which predicted that the electromagnetic waves travel at a constant speed c, the same speed as light. Sharp Einstein could immediately guessed that light must be a kind of electromagnetic wave. Concentrating on his riddle with his deep 'thought experiments', he could solve one part of the problem: that is no one can fly at that speed of light because it does not make sense.
As he recounted later: “If I pursue a beam of light with the velocity c, I should observe such a beam of light as a spatially oscillatory electromagnetic field at rest. However, there seems to be no such thing, whether on the basis of experience or according to Maxwell's equation.”
Now he need to figure out why, and what happens if one travels at high speed near c, the the speed of light. Suddenly the riddle which seemed hopeless and impossible before, became very intriguing and exciting for him. He used his imagination and 'thought experiments' to solve the problem. He found some additional clues.
There were many attempts by eminent scientists like J.J. Thomson (1881) and others to understand how the mass of a charged object depends on the electrostatic field. This concept was called electromagnetic mass, and was considered as being dependent on velocity and direction as well.
For this some physicists have postulated different equations showing how mass increases inversely with the square of c when energy is imparted to it. All of these developments may not be fully known to Einstein at that time as he was not associated with any professional physicists and was working on his own in isolation. The research scientist, Merry Currie had another riddle of her own.
While working on radioactive materials, she observed that these materials were transmitting huge amount of radio active energy, the source of which remained a mystery. Was it possible that the radioactive energy was obtained at the expense of tiny bit of the radio active materials?
There were also other clues. Since light was believed to be wave, it was believed that light needed some kind of media (like the media water and air for sound waves). For this, the scientists believed that some media was all around us at absolute rest and that it also filled the vacuum of space through which light flows.
They named that media "aether," after the Greek god of light. In 1881, two American scientists, Michelson and Morley, created an experiment and tried to prove the theory that aether existed. Their experiment was quite simple. Since, the earth travels around the Sun at a speed of more than 100,000 km per hour apparently through aether, it would cause an “wind of eather" in the same way that there seems to be a “wind of air” outside a moving car.
They tried to measure the relative speed of the earth in this “aether wind” at various directions and at various times of the year in order to determine the relative speed of light. But they simply could not detect the relative speed of the earth against this aether (at rest) and could not find the slightest difference of speed of light.
The result was very puzzling to the scientific community, and nobody had any explanation. One explanation was offered by Fitzgerald and Lorentz who proposed the hypothesis that a body in motion is actually shortened in the direction of motion by a certain proportion depending on the velocity. Te amount of contraction was to be just enough to account for the negative results of the Michelson-Morley experiment.
Of course this shortening could never be detected, even if it actually occurs, because any rod of measurement would also be shortened proportionately. All the Michelson-Morley experiment has proved was that relative to the earth the velocity of light is same in all direction, and that there is nothing called 'absolute rest' as proposed by Newton.
Considering all these available data, Einstein tried to come up with a theory which will answer all these riddles. However, there was another big puzzle to solve. Maxwell has proposed constant velocity c for electromagnetic waves. However the problem was, speed always had to be measured relative to something.
But what was this speed relative to in vacuum, in empty space, that is? That remained an unanswered question. Recalling his mental experiment of the railway carriage traveling at a speed of v and the passenger moving inside with a velocity w, Einstein tried to do 'thought experiments' by replacing the man (with velocity w) with a ray of light (with constant velocity c).
He found that it becomes incompatible with the Galilean relativity unless he considers the velocity of light same relative to the railway carriage and the railway station at the same time. By this time, it became clear to Einstein that the speed of light must be independent of the speed of the observer as well as of the speed of the source of the light. That would also mean that everyone in the universe, no matter how fast they were moving, would always observe the speed of light as constant c.
That goes against all normal Newtonian logic, but that must be true as otherwise you cannot solve the problem.
Confident of his logic, he boldly proposed that the velocity of light c must be constant 'relative to everything'. They asked, what do you mean by 'relative to everything?'
He said, it means exactly that, it is 'relative to everything'; c is a true universal constant. And that assumption basically solved the whole problem. Because once we accept this hypothesis, and are willing to discard just about everything else to make sure it holds true, we can end up with 'special theory of relativity' without a whole lot of mathematics, that is, if we know what we are doing. And that is what Einstein did.
The year 1905 is known as the ‘Miracle Year’ of Einstein. That year he submitted his Doctorate thesis and 4 of his major papers which eventually altered the very fabric of modern physics. The paper dealing with the famous equation was his last paper, titled 'Does the Inertia of a Body Depend Upon its Energy Content?' The paper was submitted in September 1905 as a follow up paper of his 'Special Theory of Relativity' submitted earlier in June 1905.
It may be noted that Einstein did not actually formulate exactly the formula E=mc2 in his paper. He even did not use the term E for energy, he used term L instead. In the paper he stated that if a body gives off the energy L in the form of radiation, its mass diminishes by L/c2 and that the inertua of a body represents its energy content.
This is of course is another way of saying the same thing, and the equation E=mc2 can easily be deduced from Einstein's prophetic statement. Importantly, Einstein was the first to have correctly deduced the mass–energy equivalence formula for the entire universe. Instead of proof, he made the statement that the validity of the equation may be tested by experiments.
Nearly all previous authors thought that the energy that contributes to mass comes only from electromagnetic fields. It may be said that while others were trying to write papers based on their mathematical derivations, Einstein was trying to find a natural law for the universe. That is where his greatness lies.
In this proposal, we see that Einstein's solution to the problem was simple and at the same time very profound. More than a mathematical genius, it shows his courage of imagination and the purity of thought.
What may be the secret of his great success? When asked, he used to say, "I have no special talents. I am only passionately curious". While it shows his humility, it also show a truth about what his being passionately curious. He was indeed passionately curious about solving the problem.
He was not concerned about time. His chasing the riddle of light for ten years proves that. As we see, Einstein used imaginative 'thought experiments' and was working all by himself in isolation to other professional physicists. In this case, we may say that he could solve the problem because he already sensed the answer through his imagination.
He was just looking for the process that will give him the answer. And the process told him that in order to find the answer he was looking for, he must take the velocity of light c as a universal constant . Einstein himself often used to say that "Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution."
In his evolution of the mass and energy equivalence, we clearly see how this is true. While the knowledge was available to all the scientists, it was only Einstein who could solve the puzzle with his imagination. As we see, his hypothesis that the speed of light is constant relative to everything was evolved not out of intense mathematical analysis but it came out of his strength of imagination and his courage to think against the flow.
[End of Article about e=mc2]
___________________________________________________________________________
3 EVERYDAY INVENTIONS EINSTEIN MADE POSSIBLE
By the Thales Group
What did Albert Einstein invent?Albert Einstein was not an inventor in the sense of da Vinci, Bell, or Edison.
Yet, he is recognized as one of the greatest physicists of all time and a genius for many.
This talented and fiercely independent mathematician and thinker changed how we see the universe through his theories and vision of physics.
In November 1915, Albert Einstein gave a series of lectures on his general theory of relativity at the Royal Prussian Academy of Sciences in Berlin.
It was the culmination of years of work, beginning with four groundbreaking papers in 1905:
Just think about it.
Three major inventions derived from Einstein's discoveries But these theories weren't confined to the lab. Since Einstein gave his lectures, what impact have his discoveries had on our everyday lives in the century?
1. Satnavs and Google Maps:
It's hard to get lost because of GPS - it allows our satnavs (satellite navigation systems) and smartphone map apps to tell us the quickest route to the restaurant or the beach.
But if it weren't for Einstein's general theory of relativity, we wouldn't know to consider relativity's effects when synchronizing the network of Global Positioning System (GPS) satellites orbiting the Earth.
This fact means their data would be filled with errors, making GPS more or less useless.
Einstein's theory of relativity shows that gravity and motion can affect time.
In GPS, the satellites that locate places move fast and are far from Earth's gravity, causing time to pass faster than on the ground. This can lead to errors in GPS, but atomic clocks can accurately measure time despite the effects of relativity.
GPS is made reliable and accurate by using atomic clocks and adjusting for time differences.
2. Your phone's clock:
Most ISPs and mobile phone masts use GPS to set the time.
And with each GPS satellite containing several atomic clocks, your computer and mobile phone clocks are ultra-accurate.
Without that accuracy, you'd probably be late (or early) for every meeting.
There's more.
3. Lasers
Lasers are crucial to all these inventions and more.
Einstein's 1916 discovery of the physical principle was responsible for light amplification by stimulating the emission of radiation (the long-winded way of saying laser) that made these devices possible.
These are just three examples - virtually no corner of science and technology hasn't experienced the Einstein effect, from supercomputers and supernovas to nuclear weapons and the Big Bang.
And in our ever-more-digital world, what happens in the lab is never far from everyday life.
In the video below, stay with us and discover some amazing facts about this genius.
Re-evaluating Mileva Marić's contributions to Einstein's work:
Albert Einstein's first wife was Mileva Marić.
They met while studying physics at the Polytechnic in Zurich, Switzerland, and married in 1903. Marić was also a physicist; evidence suggests she contributed significantly to Einstein's work. However, their marriage was tumultuous, and they eventually separated in 1914, with a divorce finalized in 1919.
The extent of Mileva Marić's contribution to Einstein's work is a matter of debate among historians of science.
Some evidence suggests that Marić collaborated with Einstein on his early papers and may have contributed to his theories of relativity.
For example, in the early 1900s, Einstein and Marić worked on a paper exploring the relationship between mass and energy. The document was written in Einstein's handwriting, but some researchers believe that Marić made significant contributions to the calculations and ideas presented in the paper.
There are also letters between Einstein and Marić that suggest they discussed physics and collaborated on other papers. In one letter, Einstein refers to "our work on relative motion," which some historians interpret as evidence of a joint project between the two.
However, there is also evidence that Marić's contributions to Einstein's work were overstated in some accounts. Some argue that the available evidence does not definitively prove that Marić made significant contributions to Einstein's theories of relativity.
Einstein's biography in a nutshell:
Albert Einstein was a German-born physicist and one of the most influential scientists of the 20th century. He was born in Ulm, Germany, in 1879, and his contributions to theoretical physics have revolutionized our understanding of the universe.
Albert Einstein's education:
He received his primary education at a Catholic elementary school in Munich and later attended the Luitpold Gymnasium, where he was given advanced schooling. After his family moved to Italy, he stayed in Munich to finish his education. Einstein struggled with the school's rote learning methods and eventually left to join his family.
Einstein furthered his education at the Argovian cantonal school in Aarau, Switzerland, and excelled, especially in physics and mathematics. He graduated from the Federal Polytechnic School in Zurich.
In 1933, due to persecution by the Nazi regime and as a Jew, Einstein emigrated to the United States and renounced his German citizenship. He later became a naturalized US citizen in 1940.
Einstein passed away on April 18, 1955, at 76, due to complications related to an abdominal aortic aneurysm (Princeton, NJ, USA).
Einstein's legacy extends far beyond his scientific achievements. He was also a passionate advocate for peace and civil rights, using his platform to promote social justice causes and raise awareness about issues affecting humanity.
Einstein was also a skilled violinist and a prolific writer.
He published over 300 scientific papers and over 150 non-scientific works during his lifetime.
His work has profoundly impacted modern physics and influenced countless scientists, engineers, and thinkers.
So, if you're wondering, "What is Albert Einstein famous for?" it's his immense contributions to the field of physics and his theory of relativity which fundamentally changed our understanding of the universe.
Let's discover Albert Einstein: 22 surprising facts about Him:
What did Albert Einstein invent?Albert Einstein was not an inventor in the sense of da Vinci, Bell, or Edison.
Yet, he is recognized as one of the greatest physicists of all time and a genius for many.
This talented and fiercely independent mathematician and thinker changed how we see the universe through his theories and vision of physics.
In November 1915, Albert Einstein gave a series of lectures on his general theory of relativity at the Royal Prussian Academy of Sciences in Berlin.
It was the culmination of years of work, beginning with four groundbreaking papers in 1905:
Just think about it:
He published these papers when he was just 26.
Science would never be the same.
Ten years later, Einstein further shook the physics world by theorizing that space and time are dynamic and distorted, affecting how objects and light move.
This supposition was his general theory of relativity - his unified description of gravity.
(Find a plain English primer on his main theories here.)
Three major inventions derived from Einstein's discoveries But these theories weren't confined to the lab.
Since Einstein gave his lectures, what impact have his discoveries had on our everyday lives in the century?
1. Satnavs and Google Maps:
It's hard to get lost because of GPS - it allows our satnavs (satellite navigation systems) and smartphone map apps to tell us the quickest route to the restaurant or the beach.
But if it weren't for Einstein's general theory of relativity, we wouldn't know to consider relativity's effects when synchronizing the network of Global Positioning System (GPS) satellites orbiting the Earth.
This fact means their data would be filled with errors, making GPS more or less useless.
Einstein's theory of relativity shows that gravity and motion can affect time.
In GPS, the satellites that locate places move fast and are far from Earth's gravity, causing time to pass faster than on the ground. This can lead to errors in GPS, but atomic clocks can accurately measure time despite the effects of relativity.
GPS is made reliable and accurate by using atomic clocks and adjusting for time differences.
2. Your phone's clock:
Most ISPs and mobile phone masts use GPS to set the time. And with each GPS satellite containing several atomic clocks, your computer and mobile phone clocks are ultra-accurate.
Without that accuracy, you'd probably be late (or early) for every meeting.
There's more:
3. Lasers:
Lasers are crucial to all these inventions and more.
Einstein's 1916 discovery of the physical principle was responsible for light amplification by stimulating the emission of radiation (the long-winded way of saying laser) that made these devices possible.
These are just three examples - virtually no corner of science and technology hasn't experienced the Einstein effect, from supercomputers and supernovas to nuclear weapons and the Big Bang.
And in our ever-more-digital world, what happens in the lab is never far from everyday life.
In the video below, stay with us and discover some amazing facts about this genius.
Re-evaluating Mileva Marić's contributions to Einstein's work:
Albert Einstein's first wife was Mileva Marić.
They met while studying physics at the Polytechnic in Zurich, Switzerland, and married in 1903. Marić was also a physicist; evidence suggests she contributed significantly to Einstein's work. However, their marriage was tumultuous, and they eventually separated in 1914, with a divorce finalized in 1919.
The extent of Mileva Marić's contribution to Einstein's work is a matter of debate among historians of science.
Some evidence suggests that Marić collaborated with Einstein on his early papers and may have contributed to his theories of relativity.
For example, in the early 1900s, Einstein and Marić worked on a paper exploring the relationship between mass and energy. The document was written in Einstein's handwriting, but some researchers believe that Marić made significant contributions to the calculations and ideas presented in the paper.
There are also letters between Einstein and Marić that suggest they discussed physics and collaborated on other papers. In one letter, Einstein refers to "our work on relative motion," which some historians interpret as evidence of a joint project between the two.
However, there is also evidence that Marić's contributions to Einstein's work were overstated in some accounts. Some argue that the available evidence does not definitively prove that Marić made significant contributions to Einstein's theories of relativity.
Einstein's biography in a nutshell:
Albert Einstein was a German-born physicist and one of the most influential scientists of the 20th century. He was born in Ulm, Germany, in 1879, and his contributions to theoretical physics have revolutionized our understanding of the universe.
Albert Einstein's education:
He received his primary education at a Catholic elementary school in Munich and later attended the Luitpold Gymnasium, where he was given advanced schooling. After his family moved to Italy, he stayed in Munich to finish his education. Einstein struggled with the school's rote learning methods and eventually left to join his family.
Einstein furthered his education at the Argovian cantonal school in Aarau, Switzerland, and excelled, especially in physics and mathematics. He graduated from the Federal Polytechnic School in Zurich.
In 1933, due to persecution by the Nazi regime and as a Jew, Einstein emigrated to the United States and renounced his German citizenship. He later became a naturalized US citizen in 1940.
Einstein passed away on April 18, 1955, at 76, due to complications related to an abdominal aortic aneurysm (Princeton, NJ, USA).
Einstein's legacy extends far beyond his scientific achievements.
So, if you're wondering, "What is Albert Einstein famous for?" it's his immense contributions to the field of physics and his theory of relativity which fundamentally changed our understanding of the universe.
[End of Article #2]
___________________________________________________________________________
Albert Einstein (Wikipedia)
Albert Einstein (German: 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who is widely held to be one of the greatest and most influential scientists of all time.
Best known for developing the theory of relativity, Einstein also made important contributions to quantum mechanics, and was thus a central figure in the revolutionary reshaping of the scientific understanding of nature that modern physics accomplished in the first decades of the twentieth century.
His mass–energy equivalence formula E = mc2, which arises from relativity theory, has been called "the world's most famous equation". He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the development of quantum theory.
His work is also known for its influence on the philosophy of science/ In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World, Einstein was ranked the greatest physicist of all time. His intellectual achievements and originality have made the word Einstein broadly synonymous with genius.
Born in the German Empire, Einstein moved to Switzerland in 1895, forsaking his German citizenship (as a subject of the Kingdom of Württemberg) the following year. In 1897, at the age of seventeen, he enrolled in the mathematics and physics teaching diploma program at the Swiss Federal polytechnic school in Zürich, graduating in 1900. In 1901, he acquired Swiss citizenship, which he kept for the rest of his life.
In 1903, he secured a permanent position at the Swiss Patent Office in Bern. In 1905, he submitted a successful PhD dissertation to the University of Zurich. In 1914, he moved to Berlin in order to join the Prussian Academy of Sciences and the Humboldt University of Berlin.
In 1917, he became director of the Kaiser Wilhelm Institute for Physics; he also became a German citizen again, this time as a subject of the Kingdom of Prussia. In 1933, while he was visiting the United States, Adolf Hitler came to power in Germany.
Horrified by the Nazi "war of extermination" against his fellow Jews, Einstein decided to remain in the US, and was granted American citizenship in 1940.
On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential German nuclear weapons program and recommending that the US begin similar research. Einstein supported the Allies but generally viewed the idea of nuclear weapons with great dismay.
In 1905, a year sometimes described as his annus mirabilis (miracle year), Einstein published four groundbreaking papers. These outlined a theory of the photoelectric effect, explained Brownian motion, introduced his special theory of relativity—a theory which addressed the inability of classical mechanics to account satisfactorily for the behavior of the electromagnetic field—and demonstrated that if the special theory is correct, mass and energy are equivalent to each other.
In 1915, he proposed a general theory of relativity that extended his system of mechanics to incorporate gravitation. A cosmological paper that he published the following year laid out the implications of general relativity for the modeling of the structure and evolution of the universe as a whole.
The middle part of his career also saw him making important contributions to statistical mechanics and quantum theory. Especially notable was his work on the quantum physics of radiation, in which light consists of particles, subsequently called photons.
For much of the last phase of his academic life, Einstein worked on two endeavors that proved ultimately unsuccessful.
Life and career:
Childhood, youth and education:
See also: Einstein family
Albert Einstein was born in Ulm, in the Kingdom of Württemberg in the German Empire, on 14 March 1879. His parents, secular Ashkenazi Jews, were Hermann Einstein, a salesman and engineer, and Pauline Koch.
In 1880, the family moved to Munich's borough of Ludwigsvorstadt-Isarvorstadt, where Einstein's father and his uncle Jakob founded Elektrotechnische Fabrik J. Einstein & Cie, a company that manufactured electrical equipment based on direct current.
Albert attended a Catholic elementary school in Munich from the age of five. When he was eight, he was transferred to the Luitpold-Gymnasium (now known as the Albert-Einstein-Gymnasium [de]) where he received advanced primary and then secondary school education.
In 1894, Hermann and Jakob's company tendered for a contract to install electric lighting in Munich, but without success—they lacked the capital that would have been required to update their technology from direct current to the more efficient, alternating current alternative.
The failure of their bid forced them to sell their Munich factory and search for new opportunities elsewhere. The Einstein family moved to Italy, first to Milan and a few months later to Pavia, where they settled in Palazzo Cornazzani. Einstein, then fifteen, stayed behind in Munich in order to finish his schooling.
His father wanted him to study electrical engineering, but he was a fractious pupil who found the Gymnasium's regimen and teaching methods far from congenial. He later wrote that the school's policy of strict rote learning was harmful to creativity.
At the end of December 1894, a letter from a doctor persuaded the Luitpold's authorities to release him from its care, and he joined his family in Pavia. While in Italy as a teenager, he wrote an essay entitled "On the Investigation of the State of the Ether in a Magnetic Field".
Einstein excelled at physics and mathematics from an early age, and soon acquired the mathematical expertise normally only found in a child several years his senior. He began teaching himself algebra, calculus and Euclidean geometry when he was twelve; he made such rapid progress that he discovered an original proof of the Pythagorean theorem before his thirteenth birthday.
A family tutor, Max Talmud, said that only a short time after he had given the twelve year old Einstein a geometry textbook, the boy "had worked through the whole book. He thereupon devoted himself to higher mathematics ... Soon the flight of his mathematical genius was so high I could not follow."
Einstein recorded that he had "mastered integral and differential calculus" while still just fourteen. His love of algebra and geometry was so great that at twelve, he was already confident that nature could be understood as a "mathematical structure".
At thirteen, when his range of enthusiasms had broadened to include music and philosophy, Einstein was introduced to Kant's Critique of Pure Reason. Kant became his favorite philosopher; according to his tutor, "At the time he was still a child, only thirteen years old, yet Kant's works, incomprehensible to ordinary mortals, seemed to be clear to him."
In 1895, at the age of sixteen, Einstein sat the entrance examination for the Federal polytechnic school (later the Eidgenössische Technische Hochschule, ETH) in Zürich, Switzerland. He failed to reach the required standard in the general part of the test, but performed with distinction in physics and mathematics.
On the advice of the polytechnic's principal, he completed his secondary education at the Argovian cantonal school (a gymnasium) in Aarau, Switzerland, graduating in 1896.
While lodging in Aarau with the family of Jost Winteler, he fell in love with Winteler's daughter, Marie. (His sister, Maja, later married Winteler's son Paul.)
In January 1896, with his father's approval, Einstein renounced his citizenship of the German Kingdom of Württemberg in order to avoid conscription into military service.
The Matura (graduation for the successful completion of higher secondary schooling) awarded to him in the September of that year acknowledged him to have performed well across most of the curriculum, allotting him a top grade of 6 for history, physics, algebra, geometry, and descriptive geometry.
At seventeen, he enrolled in the four-year mathematics and physics teaching diploma program at the Federal polytechnic school. Marie Winteler, a year older than him, took up a teaching post in Olsberg, Switzerland.
The five other polytechnic school freshmen following the same course as Einstein included just one woman, a twenty year old Serbian, Mileva Marić. Over the next few years, the pair spent many hours discussing their shared interests and learning about topics in physics that the polytechnic school's lectures did not cover.
In his letters to Marić, Einstein confessed that exploring science with her by his side was much more enjoyable than reading a textbook in solitude. Eventually the two students became not only friends but also lovers.
Historians of physics are divided on the question of the extent to which Marić contributed to the insights of Einstein's annus mirabilis publications. There is at least some evidence that he was influenced by her scientific ideas, but there are scholars who doubt whether her impact on his thought was of any great significance at all.
Marriages, relationships and children:
Correspondence between Einstein and Marić, discovered and published in 1987, revealed that in early 1902, while Marić was visiting her parents in Novi Sad, she gave birth to a daughter, Lieserl. When Marić returned to Switzerland it was without the child, whose fate is uncertain.
A letter of Einstein's that he wrote in September 1903 suggests that the girl was either given up for adoption or died of scarlet fever in infancy.
Einstein and Marić married in January 1903. In May 1904, their son Hans Albert was born in Bern, Switzerland. Their son Eduard was born in Zürich in July 1910. In letters that Einstein wrote to Marie Winteler in the months before Eduard's arrival, he described his love for his wife as "misguided" and mourned the "missed life" that he imagined he would have enjoyed if he had married Winteler instead: "I think of you in heartfelt love every spare minute and am so unhappy as only a man can be."
In 1912, Einstein entered into a relationship with Elsa Löwenthal, who was both his first cousin on his mother's side and his second cousin on his father's.
When Marić learned of his infidelity soon after moving to Berlin with him in April 1914, she returned to Zürich, taking Hans Albert and Eduard with her. Einstein and Marić were granted a divorce on 14 February 1919 on the grounds of having lived apart for five years.
As part of the divorce settlement, Einstein agreed that if he were to win a Nobel Prize, he would give the money that he received to Marić; she had to wait only two years before her foresight in extracting this promise from him was rewarded.
Einstein married Löwenthal in 1919. In 1923, he began a relationship with a secretary named Betty Neumann, the niece of his close friend Hans Mühsam. Löwenthal nevertheless remained loyal to him, accompanying him when he emigrated to the United States in 1933.
In 1935, she was diagnosed with heart and kidney problems. She died in December 1936.
A volume of Einstein's letters released by Hebrew University of Jerusalem in 2006 added further names to the catalog of women with whom he was romantically involved. They included:
After being widowed, Einstein was briefly in a relationship with Margarita Konenkova, thought by some to be a Russian spy; her husband, the Russian sculptor Sergei Konenkov, created the bronze bust of Einstein at the Institute for Advanced Study at Princeton.
Following an episode of acute mental illness at about the age of twenty, Einstein's son Eduard was diagnosed with schizophrenia. He spent the remainder of his life either in the care of his mother or in temporary confinement in an asylum. After her death, he was committed permanently to Burghölzli, the Psychiatric University Hospital in Zürich.
1902–1909: Assistant at the Swiss Patent Office:
Einstein graduated from the Federal polytechnic school in 1900, duly certified as competent to teach mathematics and physics. His successful acquisition of Swiss citizenship in February 1901 was not followed by the usual sequel of conscription; the Swiss authorities deemed him medically unfit for military service.
He found that Swiss schools too appeared to have no use for him, failing to offer him a teaching position despite the almost two years that he spent applying for one. Eventually it was with the help of Marcel Grossmann's father that he secured a post in Bern at the Swiss Patent Office, as an assistant examiner – level III.
Patent applications that landed on Einstein's desk for his evaluation included ideas for a gravel sorter and an electric typewriter. His employers were pleased enough with his work to make his position permanent in 1903, although they did not think that he should be promoted until he had "fully mastered machine technology". It is conceivable that his labors at the patent office had a bearing on his development of his special theory of relativity.
He arrived at his revolutionary ideas about space, time and light through thought experiments about the transmission of signals and the synchronization of clocks, matters which also figured in some of the inventions submitted to him for assessment.
In 1902, Einstein and some friends whom he had met in Bern formed a group that held regular meetings to discuss science and philosophy. Their choice of a name for their club, the Olympia Academy, was an ironic comment upon its far from Olympian status.
Sometimes they were joined by Marić, who limited her participation in their proceedings to careful listening.
The thinkers whose works they reflected upon included Henri Poincaré, Ernst Mach and David Hume, all of whom significantly influenced Einstein's own subsequent ideas and beliefs.
1900–1905: First scientific papers
Einstein's first paper, "Folgerungen aus den Capillaritätserscheinungen" ("Conclusions drawn from the phenomena of capillarity"), in which he proposed a model of intermolecular attraction that he afterwards disavowed as worthless, was published in the journal Annalen der Physik in 1900.
His 24-page doctoral dissertation also addressed a topic in molecular physics. Titled "Eine neue Bestimmung der Moleküldimensionen" ("A New Determination of Molecular Dimensions") and dedicated to his friend Marcel Grossman, it was completed on 30 April 1905 and approved by Professor Alfred Kleiner of the University of Zurich three months later.
(Einstein was formally awarded his PhD on 15 January 1906.)
Four other pieces of work that Einstein completed in 1905--his famous papers on the photoelectric effect, Brownian motion, his special theory of relativity and the equivalence of mass and energy—have led to the year's being celebrated as an annus mirabilis for physics almost as wonderful as 1666 (the year in which Isaac Newton experienced his greatest epiphanies). The publications deeply impressed Einstein's contemporaries.
1908–1933: Early academic career:
Einstein's sabbatical as a civil servant approached its end in 1908, when he secured a junior teaching position at the University of Bern.
In 1909, a lecture on relativistic electrodynamics that he gave at the University of Zurich, much admired by Alfred Kleiner, led to Zürich's luring him away from Bern with a newly created associate professorship.
Promotion to a full professorship followed in April 1911, when he accepted a chair at the German Charles-Ferdinand University in Prague, a move which required him to become an Austrian citizen of the Austro-Hungarian Empire. His time in Prague saw him producing eleven research papers.
In July 1912, he returned to his alma mater, the ETH Zurich, to take up a chair in theoretical physics. His teaching activities there centred on thermodynamics and analytical mechanics, and his research interests included the molecular theory of heat, continuum mechanics and the development of a relativistic theory of gravitation.
In his work on the latter topic, he was assisted by his friend, Marcel Grossmann, whose knowledge of the kind of mathematics required was greater than his own.
In the spring of 1913, two German visitors, Max Planck and Walther Nernst, called upon Einstein in Zürich in the hope of persuading him to relocate to Berlin. They offered him membership of the Prussian Academy of Sciences, the directorship of the planned Kaiser Wilhelm Institute for Physics and a chair at the Humboldt University of Berlin that would allow him to pursue his research supported by a professorial salary but with no teaching duties to burden him.
Their invitation was all the more appealing to him because Berlin happened to be the home of his latest girlfriend, Elsa Löwenthal. He duly joined the Academy on 24 July 1913, and moved into an apartment in the Berlin district of Dahlem on 1 April 1914. He was installed in his Humboldt University position shortly thereafter.
The outbreak of the First World War in July 1914 marked the beginning of Einstein's gradual estrangement from the nation of his birth.
When the "Manifesto of the Ninety-Three" was published in October 1914—a document signed by a host of prominent German thinkers that justified Germany's belligerence—Einstein was one of the few German intellectuals to distance himself from it and sign the alternative, eirenic "Manifesto to the Europeans" instead.
But this expression of his doubts about German policy did not prevent him from being elected to a two-year term as president of the German Physical Society in 1916. And when the Kaiser Wilhelm Institute for Physics opened its doors the following year—its foundation delayed because of the war—Einstein was appointed its first director, just as Planck and Nernst had promised.
Einstein was elected a Foreign Member of the Royal Netherlands Academy of Arts and Sciences in 1920, and a Foreign Member of the Royal Society in 1921. In 1922, he was awarded the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect".
At this point some physicists still regarded the general theory of relativity sceptically, and the Nobel citation displayed a degree of doubt even about the work on photoelectricity that it acknowledged: it did not assent to Einstein's notion of the particulate nature of light, which only won over the entire scientific community when S. N. Bose derived the Planck spectrum in 1924.
That same year, Einstein was elected an International Honorary Member of the American Academy of Arts and Sciences. Britain's closest equivalent of the Nobel award, the Royal Society's Copley Medal, was not hung around Einstein's neck until 1925. He was elected an International Member of the American Philosophical Society in 1930.
Einstein resigned from the Prussian Academy in March 1933. His accomplishments in Berlin had included the completion of the general theory of relativity, proving the Einstein–de Haas effect, contributing to the quantum theory of radiation, and the development of Bose–Einstein statistics.
1919: Putting general relativity to the test
In 1907, Einstein reached a milestone on his long journey from his special theory of relativity to a new idea of gravitation with the formulation of his equivalence principle, which asserts that an observer in an infinitesimally small box falling freely in a gravitational field would be unable to find any evidence that the field exists.
In 1911, he used the principle to estimate the amount by which a ray of light from a distant star would be bent by the gravitational pull of the Sun as it passed close to the Sun's photosphere (that is, the Sun's apparent surface).
He reworked his calculation in 1913, having now found a way to model gravitation with the Riemann curvature tensor of a non-Euclidean four-dimensional spacetime.
By the fall of 1915, his reimagining of the mathematics of gravitation in terms of Riemannian geometry was complete, and he applied his new theory not just to the behavior of the Sun as a gravitational lens but also to another astronomical phenomenon, the precession of the perihelion of Mercury (a slow drift in the point in Mercury's elliptical orbit at which it approaches the Sun most closely).
A total eclipse of the Sun that took place on 29 May 1919 provided an opportunity to put his theory of gravitational lensing to the test, and observations performed by Sir Arthur Eddington yielded results that were consistent with his calculations.
Eddington's work was reported at length in newspapers around the world. On 7 November 1919, for example, the leading British newspaper, The Times, printed a banner headline that read: "Revolution in Science – New Theory of the Universe – Newtonian Ideas Overthrown".
1921–1923: Coming to terms with fame
With Eddington's eclipse observations widely reported not just in academic journals but by the popular press as well, Einstein became "perhaps the world's first celebrity scientist", a genius who had shattered a paradigm that had been basic to physicists' understanding of the universe since the seventeenth century.
Einstein began his new life as an intellectual icon in America, where he arrived on 2 April 1921. He was welcomed to New York City by Mayor John Francis Hylan, and then spent three weeks giving lectures and attending receptions.
He spoke several times at Columbia University and Princeton, and in Washington, he visited the White House with representatives of the National Academy of Sciences. He returned to Europe via London, where he was the guest of the philosopher and statesman Viscount Haldane.
He used his time in the British capital to meet several people prominent in British scientific, political or intellectual life, and to deliver a lecture at King's College. In July 1921, he published an essay, "My First Impression of the U.S.A.", in which he sought to sketch the American character, much as had Alexis de Tocqueville in Democracy in America (1835).
He wrote of his transatlantic hosts in highly approving terms: "What strikes a visitor is the joyous, positive attitude to life ... The American is friendly, self-confident, optimistic, and without envy."
In 1922, Einstein's travels were to the old world rather than the new. He devoted six months to a tour of Asia that saw him speaking in Japan, Singapore and Sri Lanka (then known as Ceylon).
After his first public lecture in Tokyo, he met Emperor Yoshihito and his wife at the Imperial Palace, with thousands of spectators thronging the streets in the hope of catching a glimpse of him. (In a letter to his sons, he wrote that Japanese people seemed to him to be generally modest, intelligent and considerate, and to have a true appreciation of art. But his picture of them in his diary was less flattering: "[the] intellectual needs of this nation seem to be weaker than their artistic ones – natural disposition?" His journal also contains views of China and India which were uncomplimentary.
Of Chinese people, he wrote that "even the children are spiritless and look obtuse... It would be a pity if these Chinese supplant all other races. For the likes of us the mere thought is unspeakably dreary".)
He was greeted with even greater enthusiasm on the last leg of his tour, in which he spent twelve days in Mandatory Palestine, newly entrusted to British rule by the League of Nations in the aftermath of the First World War. Sir Herbert Samuel, the British High Commissioner, welcomed him with a degree of ceremony normally only accorded to a visiting head of state, including a cannon salute.
One reception held in his honor was stormed by people determined to hear him speak: he told them that he was happy that Jews were beginning to be recognized as a force in the world.
Einstein's decision to tour the eastern hemisphere in 1922 meant that he was unable to go to Stockholm in the December of that year to participate in the Nobel prize ceremony. His place at the traditional Nobel banquet was taken by a German diplomat, who gave a speech praising him not only as a physicist but also as a campaigner for peace.
A two week visit to Spain that he undertook in 1923 saw him collecting another award, a membership of the Spanish Academy of Sciences signified by a diploma handed to him by King Alfonso XIII. (His Spanish trip also gave him a chance to meet a fellow Nobel laureate, the neuroanatomist Santiago Ramón y Cajal.)
1922–1932: Serving the League of Nations
Einstein at a session of the International Committee on Intellectual Cooperation (League of Nations) of which he was a member from 1922 to 1932. From 1922 until 1932, with the exception of a few months in 1923 and 1924, Einstein was a member of the Geneva-based International Committee on Intellectual Cooperation of the League of Nations, a group set up by the League to encourage scientists, artists, scholars, teachers and other people engaged in the life of the mind to work more closely with their counterparts in other countries.
He was appointed as a German delegate rather than as a representative of Switzerland because of the machinations of two Catholic activists, Oskar Halecki and Giuseppe Motta.
By persuading Secretary General Eric Drummond to deny Einstein the place on the committee reserved for a Swiss thinker, they created an opening for Gonzague de Reynold, who used his League of Nations position as a platform from which to promote traditional Catholic doctrine.
Einstein's former physics professor Hendrik Lorentz and the Polish chemist Marie Curie were also members of the committee.
1925: Touring South America:
In March and April 1925, Einstein and his wife visited South America, where they spent about a week in Brazil, a week in Uruguay and a month in Argentina. Their tour was suggested by Jorge Duclout (1856–1927) and Mauricio Nirenstein (1877–1935) with the support of several Argentine scholars, including Julio Rey Pastor, Jakob Laub, and Leopoldo Lugones. and was financed primarily by the Council of the University of Buenos Aires and the Asociación Hebraica Argentina (Argentine Hebraic Association) with a smaller contribution from the Argentine-Germanic Cultural Institution.
1930–1931: Touring the US:
In December 1930, Einstein began another significant sojourn in the United States, drawn back to the US by the offer of a two month research fellowship at the California Institute of Technology.
Caltech supported him in his wish that he should not be exposed to quite as much attention from the media as he had experienced when visiting the US in 1921, and he therefore declined all the invitations to receive prizes or make speeches that his admirers poured down upon him. But he remained willing to allow his fans at least some of the time with him that they requested.
After arriving in New York City, Einstein was taken to various places and events, including Chinatown, a lunch with the editors of The New York Times, and a performance of Carmen at the Metropolitan Opera, where he was cheered by the audience on his arrival.
During the days following, he was given the keys to the city by Mayor Jimmy Walker and met Nicholas Murray Butler, the president of Columbia University, who described Einstein as "the ruling monarch of the mind".
Harry Emerson Fosdick, pastor at New York's Riverside Church, gave Einstein a tour of the church and showed him a full-size statue that the church made of Einstein, standing at the entrance. Also during his stay in New York, he joined a crowd of 15,000 people at Madison Square Garden during a Hanukkah celebration.
Einstein next traveled to California, where he met Caltech president and Nobel laureate Robert A. Millikan. His friendship with Millikan was "awkward", as Millikan "had a penchant for patriotic militarism", where Einstein was a pronounced pacifist.
During an address to Caltech's students, Einstein noted that science was often inclined to do more harm than good.
This aversion to war also led Einstein to befriend author Upton Sinclair and film star Charlie Chaplin, both noted for their pacifism. Carl Laemmle, head of Universal Studios, gave Einstein a tour of his studio and introduced him to Chaplin.
They had an instant rapport, with Chaplin inviting Einstein and his wife, Elsa, to his home for dinner. Chaplin said Einstein's outward persona, calm and gentle, seemed to conceal a "highly emotional temperament", from which came his "extraordinary intellectual energy".
Chaplin's film, City Lights, was to premiere a few days later in Hollywood, and Chaplin invited Einstein and Elsa to join him as his special guests. Walter Isaacson, Einstein's biographer, described this as "one of the most memorable scenes in the new era of celebrity".
Chaplin visited Einstein at his home on a later trip to Berlin and recalled his "modest little flat" and the piano at which he had begun writing his theory. Chaplin speculated that it was "possibly used as kindling wood by the Nazis".
1933: Emigration to the US
In February 1933, while on a visit to the United States, Einstein knew he could not return to Germany with the rise to power of the Nazis under Germany's new chancellor, Adolf Hitler.
While at American universities in early 1933, he undertook his third two-month visiting professorship at the California Institute of Technology in Pasadena. In February and March 1933, the Gestapo repeatedly raided his family's apartment in Berlin.
He and his wife Elsa returned to Europe in March, and during the trip, they learned that the German Reichstag had passed the Enabling Act on 23 March, transforming Hitler's government into a de facto legal dictatorship, and that they would not be able to proceed to Berlin.
Later on, they heard that their cottage had been raided by the Nazis and Einstein's personal sailboat confiscated. Upon landing in Antwerp, Belgium on 28 March, Einstein immediately went to the German consulate and surrendered his passport, formally renouncing his German citizenship. The Nazis later sold his boat and converted his cottage into a Hitler Youth camp.
Refugee status
Landing card for Einstein's 26 May 1933 arrival in Dover, England from Ostend, Belgium, enroute to Oxford.In April 1933, Einstein discovered that the new German government had passed laws barring Jews from holding any official positions, including teaching at universities.
Historian Gerald Holton describes how, with "virtually no audible protest being raised by their colleagues", thousands of Jewish scientists were suddenly forced to give up their university positions and their names were removed from the rolls of institutions where they were employed.
A month later, Einstein's works were among those targeted by the German Student Union in the Nazi book burnings, with Nazi propaganda minister Joseph Goebbels proclaiming, "Jewish intellectualism is dead." One German magazine included him in a list of enemies of the German regime with the phrase, "not yet hanged", offering a $5,000 bounty on his head.
In a subsequent letter to physicist and friend Max Born, who had already emigrated from Germany to England, Einstein wrote, "... I must confess that the degree of their brutality and cowardice came as something of a surprise."
After moving to the US, he described the book burnings as a "spontaneous emotional outburst" by those who "shun popular enlightenment", and "more than anything else in the world, fear the influence of men of intellectual independence".
Einstein was now without a permanent home, unsure where he would live and work, and equally worried about the fate of countless other scientists still in Germany. Aided by the Academic Assistance Council, founded in April 1933 by British Liberal politician William Beveridge to help academics escape Nazi persecution, Einstein was able to leave Germany.
He rented a house in De Haan, Belgium, where he lived for a few months. In late July 1933, he visited England for about six weeks at the invitation of the British Member of Parliament Commander Oliver Locker-Lampson, who had become friends with him in the preceding years.
Locker-Lampson invited him to stay near his Cromer home in a secluded wooden cabin on Roughton Heath in the Parish of Roughton, Norfolk. To protect Einstein, Locker-Lampson had two bodyguards watch over him; a photo of them carrying shotguns and guarding Einstein was published in the Daily Herald on 24 July 1933.
Locker-Lampson took Einstein to meet Winston Churchill at his home, and later, Austen Chamberlain and former Prime Minister Lloyd George. Einstein asked them to help bring Jewish scientists out of Germany. British historian Martin Gilbert notes that Churchill responded immediately, and sent his friend, physicist Frederick Lindemann, to Germany to seek out Jewish scientists and place them in British universities.
Churchill later observed that as a result of Germany having driven the Jews out, they had lowered their "technical standards" and put the Allies' technology ahead of theirs.
Einstein later contacted leaders of other nations, including Turkey's Prime Minister, İsmet İnönü, to whom he wrote in September 1933 requesting placement of unemployed German-Jewish scientists. As a result of Einstein's letter, Jewish invitees to Turkey eventually totaled over "1,000 saved individuals".
Locker-Lampson also submitted a bill to parliament to extend British citizenship to Einstein, during which period Einstein made a number of public appearances describing the crisis brewing in Europe.
In one of his speeches he denounced Germany's treatment of Jews, while at the same time he introduced a bill promoting Jewish citizenship in Palestine, as they were being denied citizenship elsewhere. In his speech he described Einstein as a "citizen of the world" who should be offered a temporary shelter in the UK.
Both bills failed, however, and Einstein then accepted an earlier offer from the Institute for Advanced Study, in Princeton, New Jersey, US, to become a resident scholar.
Resident scholar at the Institute for Advanced Study
On 3 October 1933, Einstein delivered a speech on the importance of academic freedom before a packed audience at the Royal Albert Hall in London, with The Times reporting he was wildly cheered throughout. Four days later he returned to the US and took up a position at the Institute for Advanced Study, noted for having become a refuge for scientists fleeing Nazi Germany.
At the time, most American universities, including Harvard, Princeton and Yale, had minimal or no Jewish faculty or students, as a result of their Jewish quotas, which lasted until the late 1940s.
Einstein was still undecided on his future. He had offers from several European universities, including Christ Church, Oxford, where he stayed for three short periods between May 1931 and June 1933 and was offered a five-year research fellowship (called a "studentship" at Christ Church), but in 1935, he arrived at the decision to remain permanently in the United States and apply for citizenship.
Einstein's affiliation with the Institute for Advanced Study would last until his death in 1955. He was one of the four first selected (along with John von Neumann, Kurt Gödel, and Hermann Weyl) at the new Institute. He soon developed a close friendship with Gödel; the two would take long walks together discussing their work. Bruria Kaufman, his assistant, later became a physicist.
During this period, Einstein tried to develop a unified field theory and to refute the accepted interpretation of quantum physics, both unsuccessfully. He lived in Princeton at his home from 1935 onwards. The Albert Einstein House was made a National Historic Landmark in 1976.
World War II and the Manhattan Project
See also: Einstein–Szilárd letter
In 1939, a group of Hungarian scientists that included émigré physicist Leó Szilárd attempted to alert Washington to ongoing Nazi atomic bomb research.
The group's warnings were discounted. Einstein and Szilárd, along with other refugees such as Edward Teller and Eugene Wigner, "regarded it as their responsibility to alert Americans to the possibility that German scientists might win the race to build an atomic bomb, and to warn that Hitler would be more than willing to resort to such a weapon."
To make certain the US was aware of the danger, in July 1939, a few months before the beginning of World War II in Europe, Szilárd and Wigner visited Einstein to explain the possibility of atomic bombs, which Einstein, a pacifist, said he had never considered.
He was asked to lend his support by writing a letter, with Szilárd, to President Roosevelt, recommending the US pay attention and engage in its own nuclear weapons research.
The letter is believed to be "arguably the key stimulus for the U.S. adoption of serious investigations into nuclear weapons on the eve of the U.S. entry into World War II".
In addition to the letter, Einstein used his connections with the Belgian royal family and the Belgian queen mother to get access with a personal envoy to the White House's Oval Office. Some say that as a result of Einstein's letter and his meetings with Roosevelt, the US entered the "race" to develop the bomb, drawing on its "immense material, financial, and scientific resources" to initiate the Manhattan Project.
For Einstein, "war was a disease ... [and] he called for resistance to war." By signing the letter to Roosevelt, some argue he went against his pacifist principles. In 1954, a year before his death, Einstein said to his old friend, Linus Pauling, "I made one great mistake in my life—when I signed the letter to President Roosevelt recommending that atom bombs be made; but there was some justification—the danger that the Germans would make them ..."
In 1955, Einstein and ten other intellectuals and scientists, including British philosopher Bertrand Russell, signed a manifesto highlighting the danger of nuclear weapons.
In 1960 Einstein was included posthumously as a charter member of the World Academy of Art and Science (WAAS), an organization founded by distinguished scientists and intellectuals who committed themselves to the responsible and ethical advances of science, particularly in light of the development of nuclear weapons.
US citizenship
Einstein became an American citizen in 1940. Not long after settling into his career at the Institute for Advanced Study in Princeton, New Jersey, he expressed his appreciation of the meritocracy in American culture compared to Europe.
He recognized the "right of individuals to say and think what they pleased" without social barriers. As a result, individuals were encouraged, he said, to be more creative, a trait he valued from his early education.
Einstein joined the National Association for the Advancement of Colored People (NAACP) in Princeton, where he campaigned for the civil rights of African Americans. He considered racism America's "worst disease", seeing it as "handed down from one generation to the next".
As part of his involvement, he corresponded with civil rights activist W. E. B. Du Bois and was prepared to testify on his behalf during his trial as an alleged foreign agent in 1951. When Einstein offered to be a character witness for Du Bois, the judge decided to drop the case.
In 1946, Einstein visited Lincoln University in Pennsylvania, a historically black college, where he was awarded an honorary degree. Lincoln was the first university in the United States to grant college degrees to African Americans; alumni include Langston Hughes and Thurgood Marshall.
Einstein gave a speech about racism in America, adding, "I do not intend to be quiet about it." A resident of Princeton recalls that Einstein had once paid the college tuition for a black student. Einstein has said, "Being a Jew myself, perhaps I can understand and empathize with how black people feel as victims of discrimination".
Personal views:
Political views
Main article: Political views of Albert Einstein
Albert Einstein and Elsa Einstein arriving in New York in 1921. Accompanying them are Zionist leaders Chaim Weizmann (future president of Israel), Weizmann's wife Vera Weizmann, Menahem Ussishkin, and Ben-Zion Mossinson.
In 1918, Einstein was one of the signatories of the founding proclamation of the German Democratic Party, a liberal party. Later in his life, Einstein's political view was in favor of socialism and critical of capitalism, which he detailed in his essays such as "Why Socialism?".
His opinions on the Bolsheviks also changed with time. In 1925, he criticized them for not having a "well-regulated system of government" and called their rule a "regime of terror and a tragedy in human history".
He later adopted a more moderated view, criticizing their methods but praising them, which is shown by his 1929 remark on Vladimir Lenin: "In Lenin I honor a man, who in total sacrifice of his own person has committed his entire energy to realizing social justice. I do not find his methods advisable. One thing is certain, however: men like him are theguardians and renewers of mankind's conscience."
Einstein offered and was called on to give judgments and opinions on matters often unrelated to theoretical physics or mathematics. He strongly advocated the idea of a democratic global government that would check the power of nation-states in the framework of a world federation.
He wrote "I advocate world government because I am convinced that there is no other possible way of eliminating the most terrible danger in which man has ever found himself." The FBI created a secret dossier on Einstein in 1932; by the time of his death, it was 1,427 pages long.
Einstein was deeply impressed by Mahatma Gandhi, with whom he corresponded. He described Gandhi as "a role model for the generations to come".
The initial connection was established on 27 September 1931, when Wilfrid Israel took his Indian guest V. A. Sundaram to meet his friend Einstein at his summer home in the town of Caputh. Sundaram was Gandhi's disciple and special envoy, whom Wilfrid Israel met while visiting India and visiting the Indian leader's home in 1925.
During the visit, Einstein wrote a short letter to Gandhi that was delivered to him through his envoy, and Gandhi responded quickly with his own letter. Although in the end Einstein and Gandhi were unable to meet as they had hoped, the direct connection between them was established through Wilfrid Israel.
Relationship with Zionism
In 1947, Einstein was a figurehead leader in the establishment of the Hebrew University of Jerusalem, which opened in 1925. Earlier, in 1921, he was asked by the biochemist and president of the World Zionist Organization, Chaim Weizmann, to help raise funds for the planned university.
He made suggestions for the creation of an Institute of Agriculture, a Chemical Institute and an Institute of Microbiology in order to fight the various ongoing epidemics such as malaria, which he called an "evil" that was undermining a third of the country's development. He also promoted the establishment of an Oriental Studies Institute, to include language courses given in both Hebrew and Arabic.
Einstein was not a nationalist and opposed the creation of an independent Jewish state. He felt that the waves of arriving Jews of the Aliyah could live alongside existing Arabs in Palestine.
The state of Israel was established without his help in 1948; Einstein was limited to a marginal role in the Zionist movement. Upon the death of Israeli president Weizmann in November 1952, Prime Minister David Ben-Gurion offered Einstein the largely ceremonial position of President of Israel at the urging of Ezriel Carlebach.
The offer was presented by Israel's ambassador in Washington, Abba Eban, who explained that the offer "embodies the deepest respect which the Jewish people can repose in any of its sons". Einstein wrote that he was "deeply moved", but "at once saddened and ashamed" that he could not accept it.
Religious and philosophical views
Main article: Religious and philosophical views of Albert Einstein
Einstein expounded his spiritual outlook in a wide array of writings and interviews. He said he had sympathy for the impersonal pantheistic God of Baruch Spinoza's philosophy.
He did not believe in a personal god who concerns himself with fates and actions of human beings, a view which he described as naïve. He clarified, however, that "I am not an atheist", preferring to call himself an agnostic, or a "deeply religious nonbeliever".
When asked if he believed in an afterlife, Einstein replied, "No. And one life is enough for me."
Einstein was primarily affiliated with non-religious humanist and Ethical Culture groups in both the UK and US. He served on the advisory board of the First Humanist Society of New York, and was an honorary associate of the Rationalist Association, which publishes New Humanist in Britain.
For the 75th anniversary of the New York Society for Ethical Culture, he stated that the idea of Ethical Culture embodied his personal conception of what is most valuable and enduring in religious idealism. He observed, "Without 'ethical culture' there is no salvation for humanity."
In a German-language letter to philosopher Eric Gutkind, dated 3 January 1954, Einstein wrote: "The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honorable, but still primitive legends which are nevertheless pretty childish. No interpretation no matter how subtle can (for me) change this. ... For me the Jewish religion like all other religions is an incarnation of the most childish superstitions. And the Jewish people to whom I gladly belong and with whose mentality I have a deep affinity have no different quality for me than all other people. ... I cannot see anything 'chosen' about them.
Einstein had been sympathetic toward vegetarianism for a long time. In a letter in 1930 to Hermann Huth, vice-president of the German Vegetarian Federation (Deutsche Vegetarier-Bund), he wrote: "Although I have been prevented by outward circumstances from observing a strictly vegetarian diet, I have long been an adherent to the cause in principle. Besides agreeing with the aims of vegetarianism for aesthetic and moral reasons, it is my view that a vegetarian manner of living by its purely physical effect on the human temperament would most beneficially influence the lot of mankind.
He became a vegetarian himself only during the last part of his life. In March 1954 he wrote in a letter: "So I am living without fats, without meat, without fish, but am feeling quite well this way. It almost seems to me that man was not born to be a carnivore."
Love of music:
Einstein developed an appreciation for music at an early age. In his late journals he wrote:
If I were not a physicist, I would probably be a musician. I often think in music. I live my daydreams in music. I see my life in terms of music ... I get most joy in life out of music.
His mother played the piano reasonably well and wanted her son to learn the violin, not only to instill in him a love of music but also to help him assimilate into German culture.
According to conductor Leon Botstein, Einstein began playing when he was 5. However, he did not enjoy it at that age.
When he turned 13, he discovered the violin sonatas of Mozart, whereupon he became enamored of Mozart's compositions and studied music more willingly. Einstein taught himself to play without "ever practicing systematically". He said that "love is a better teacher than a sense of duty".
At the age of 17, he was heard by a school examiner in Aarau while playing Beethoven's violin sonatas. The examiner stated afterward that his playing was "remarkable and revealing of 'great insight'". What struck the examiner, writes Botstein, was that Einstein "displayed a deep love of the music, a quality that was and remains in short supply. Music possessed an unusual meaning for this student."
Music took on a pivotal and permanent role in Einstein's life from that period on. Although the idea of becoming a professional musician himself was not on his mind at any time, among those with whom Einstein played chamber music were a few professionals, including Kurt Appelbaum, and he performed for private audiences and friends.
Chamber music had also become a regular part of his social life while living in Bern, Zürich, and Berlin, where he played with Max Planck and his son, among others. He is sometimes erroneously credited as the editor of the 1937 edition of the Köchel catalog of Mozart's work; that edition was prepared by Alfred Einstein, who may have been a distant relation.
In 1931, while engaged in research at the California Institute of Technology, he visited the Zoellner family conservatory in Los Angeles, where he played some of Beethoven and Mozart's works with members of the Zoellner Quartet.
Near the end of his life, when the young Juilliard Quartet visited him in Princeton, he played his violin with them, and the quartet was "impressed by Einstein's level of coordination and intonation".
Death:
On 17 April 1955, Einstein experienced internal bleeding caused by the rupture of an abdominal aortic aneurysm, which had previously been reinforced surgically by Rudolph Nissen in 1948. He took the draft of a speech he was preparing for a television appearance commemorating the state of Israel's seventh anniversary with him to the hospital, but he did not live to complete it.
Einstein refused surgery, saying, "I want to go when I want. It is tasteless to prolong life artificially. I have done my share; it is time to go. I will do it elegantly." He died in the Princeton Hospital early the next morning at the age of 76, having continued to work until near the end.
During the autopsy, the pathologist Thomas Stoltz Harvey removed Einstein's brain for preservation without the permission of his family, in the hope that the neuroscience of the future would be able to discover what made Einstein so intelligent.
Einstein's remains were cremated in Trenton, New Jersey, and his ashes were scattered at an undisclosed location.
In a memorial lecture delivered on 13 December 1965 at UNESCO headquarters, nuclear physicist J. Robert Oppenheimer summarized his impression of Einstein as a person: "He was almost wholly without sophistication and wholly without worldliness ... There was always with him a wonderful purity at once childlike and profoundly stubborn."
Einstein bequeathed his personal archives, library, and intellectual assets to the Hebrew University of Jerusalem in Israel.
Scientific career:
Throughout his life, Einstein published hundreds of books and articles. He published more than 300 scientific papers and 150 non-scientific ones.
On 5 December 2014, universities and archives announced the release of Einstein's papers, comprising more than 30,000 unique documents. Einstein's intellectual achievements and originality have made the word "Einstein" synonymous with "genius".
In addition to the work he did by himself he also collaborated with other scientists on additional projects including the Bose–Einstein statistics, the Einstein refrigerator and others.
There is some evidence from Einstein's writings that he collaborated with his first wife, Mileva Marić. In 13 December 1900, a first article on capillarity signed only under his name was submitted. The decision to publish only under his name seems to have been mutual, but the exact reason is unknown.
1905 – Annus Mirabilis papers:
The Annus Mirabilis papers are four articles pertaining to the photoelectric effect (which gave rise to quantum theory), Brownian motion, the special theory of relativity, and E = mc2 that Einstein published in the Annalen der Physik scientific journal in 1905.
These four works contributed substantially to the foundation of modern physics and changed views on space, time, and matter. The four papers are::
The Story Behind Einstein's Immortal Equation
It has been more than a century ago that Albert Einstein arrived at his immortal equation E=mc2. It can rightly be said that a new age in modern physics started with Albert Einstein whose legacy will stay with us for a long time to come. The equation that bears his name is as famous as Einstein himself.
Indeed, the equation has been immortalized by its utter simplicity and its profound meaning and impact in our civilization. The energy E of a body (at rest) is equal to its mass 'm' multiplied by c2 (that is c x c), where 'c' equals the speed of light (in vacuum). The equation’s message is that the mass and energy of a body are convertible, and the mass of a body measures its energy content.
We can do some simple computation by using the SI system where m = mass in kg, c = speed of light 300,000,000 (approx) (that is 3 x 108) meter per sec, and E = the energy in Joules (3.6 million Joules equals one kilowatt-hour, kWh). Taking 'm' as 1 kg, we can calculate the energy content of 1 kg of matter (any matter) as E= mc2 =1 x c2 = 1 x (3 x 108) 2 = 9x1016 Joules = 25 x10 9 kWh, that is 25.0 billion kilowatt-hours
How much energy is that? If we consider 10,000 kWh to be the average annual power consumption (833 kWh per month) of a modern household, this one kg equivalent energy will give enough energy for 2,500,000 years that is 2.5 million years.
The equation E=mc2 becomes more fundamental if we consider the unit of c, the speed of light, as 'one light year per year' in which case c2 converts to I, and the equation becomes just E=m, meaning energy and mass are equal and the same. This is the most simple, fundamental and most profound equation ever evolved by humanity.
When the full meaning of the equation was known by the general public with the equivalence of mass and energy, someone asked Einstein, how come this fact was not known to us before?
The answer given by Einstein was very simple but at the same time very profound. He said, consider a rich man who has not spent a single penny all his life. How you would know that he is rich? In case of matter, the situation is like that. We never knew that matter possesses so much energy.
His answer reads like a Buddhist Jataka story of 'Hidden Treasure' where the poor monk had an invaluable gem sewn in his garment all his life which he did not know.
Einstein formulated this equation in 1905.
The question is how Einstein has arrived at this equation? How and why others could not? Many would think that being a mathematical genius, Einstein, might have evolved the equation after intense mathematical analysis. In fact nothing is further from the truth. As a matter of fact, Einstein was neither the first person to consider the equivalence of mass and energy, nor did he actually prove it. He just proposed the equation.
In order to understand how he evolved the equation, and how and why he received all the credit and fame for E=mc2, we will have understand a bit of history of science of his time as well as a bit of the life of Albert Einstein.
Albert Einstein was born in 1879 in Germany of a Jewish family, and as a child he grew up in the city of Munich. When Albert was a child, he had a remarkable experience of his first 'wonder' of nature. When little Albert was just five years old, his father gave him a pocket compass. The compass with its needle moving in a determined way by an unknown force, made a lasting and profound impression on the future theoretical physicist. This was one of the things that drove him to study science.
When he was twelve, he experienced his second joy and 'wonder' of a different kind when somebody gave him a little book dealing with Euclidian plane geometry. The theorems like "The theorems like 'three altitudes of a triangle are concurrent', the Pythagoras theorem and others gave him so much joy and wonder, that he remembered this all his life and wrote about it in his autobiographical notes years later.
As an youth, Einstein was a discontented and an independent thinker. At home he was stimulated more by a free exchange of ideas with his liberal parents. At sixteen, he told his father that he no longer wished to be German and at the same time announced that while he loved the Jewish culture, he was severing all formal connections with the Jewish faith.
His independent readings included many and was especially thrilled with natural sciences, geometry, philosophy (Spinoza, Buddhism etc), history, music and all. He was also playing the Violin. He was inquisitive and interested to know everything. However, at the advice of his father, he decided to focus on something which will assure him a job - especially important for a Jewish boy.
Otherwise, according to his own admission, he might have ended up being a musician.
However, he was also good in science. While studying in high school, Einstein familiarized himself with the elements of mathematics. By the time he was seventeen and ready to go to college, he also studied quite a bit of college physics. A number of scientific theories and mathematical equations had been worked out by the physicists at that time.
There were however a few situations where these theories couldn't satisfactorily explain. Einstein was interested to study these riddles on his own and to offer explanations.
When there were no riddles, he used to create his own riddle. When he was sixteen (1895), one such riddle that he created for himself was this: He used to imagine what would happen if he would fly with a beam of light. If he would move at the same speed of light, would he see the light waves as frozen? Would he see himself in a mirror if he would carry a mirror with him?
That was a riddle none of the physicists were interested to bother. They had too many other important issues to bother. But Einstein was not a professional physicist, he was just a college student studying physics and mathematics. For Einstein, the riddle was very intriguing, and he became passionately inquisitive about it. During these ten years, there was probably not a single day when he was not thinking about the problem and probably not a single night when he was not going to bed with the problem in his head.
The problem remained in his conscious and subconscious mind everyday of his life till he could solve the riddle in 1905.
During these ten years, he graduated from the Polytechnic in 1900 with a diploma to teach to math and physics. However, he could not find any job and he remained unemployed for quite some time.
Finally, he could land up a job as a clerk in the Patent office. This however become a blessing in disguise for Einstein. Working in the Patent office required less demands of his time. He soon discovered that he could go back to his 'Gedanken experiments,' or 'thought experiments' (meditations) that had tantalized him so far to concentrate on solving such scientific riddles.
During this time he also met a girl named Mileva, a class mate, with whom he fell in love and they got married.
Einstein had studied Maxwell's equations of electromagnetic waves which predicted that the electromagnetic waves travel at a constant speed c, the same speed as light. Sharp Einstein could immediately guessed that light must be a kind of electromagnetic wave. Concentrating on his riddle with his deep 'thought experiments', he could solve one part of the problem: that is no one can fly at that speed of light because it does not make sense.
As he recounted later: “If I pursue a beam of light with the velocity c, I should observe such a beam of light as a spatially oscillatory electromagnetic field at rest. However, there seems to be no such thing, whether on the basis of experience or according to Maxwell's equation.”
Now he need to figure out why, and what happens if one travels at high speed near c, the the speed of light. Suddenly the riddle which seemed hopeless and impossible before, became very intriguing and exciting for him. He used his imagination and 'thought experiments' to solve the problem. He found some additional clues.
There were many attempts by eminent scientists like J.J. Thomson (1881) and others to understand how the mass of a charged object depends on the electrostatic field. This concept was called electromagnetic mass, and was considered as being dependent on velocity and direction as well.
For this some physicists have postulated different equations showing how mass increases inversely with the square of c when energy is imparted to it. All of these developments may not be fully known to Einstein at that time as he was not associated with any professional physicists and was working on his own in isolation. The research scientist, Merry Currie had another riddle of her own.
While working on radioactive materials, she observed that these materials were transmitting huge amount of radio active energy, the source of which remained a mystery. Was it possible that the radioactive energy was obtained at the expense of tiny bit of the radio active materials?
There were also other clues. Since light was believed to be wave, it was believed that light needed some kind of media (like the media water and air for sound waves). For this, the scientists believed that some media was all around us at absolute rest and that it also filled the vacuum of space through which light flows.
They named that media "aether," after the Greek god of light. In 1881, two American scientists, Michelson and Morley, created an experiment and tried to prove the theory that aether existed. Their experiment was quite simple. Since, the earth travels around the Sun at a speed of more than 100,000 km per hour apparently through aether, it would cause an “wind of eather" in the same way that there seems to be a “wind of air” outside a moving car.
They tried to measure the relative speed of the earth in this “aether wind” at various directions and at various times of the year in order to determine the relative speed of light. But they simply could not detect the relative speed of the earth against this aether (at rest) and could not find the slightest difference of speed of light.
The result was very puzzling to the scientific community, and nobody had any explanation. One explanation was offered by Fitzgerald and Lorentz who proposed the hypothesis that a body in motion is actually shortened in the direction of motion by a certain proportion depending on the velocity. Te amount of contraction was to be just enough to account for the negative results of the Michelson-Morley experiment.
Of course this shortening could never be detected, even if it actually occurs, because any rod of measurement would also be shortened proportionately. All the Michelson-Morley experiment has proved was that relative to the earth the velocity of light is same in all direction, and that there is nothing called 'absolute rest' as proposed by Newton.
Considering all these available data, Einstein tried to come up with a theory which will answer all these riddles. However, there was another big puzzle to solve. Maxwell has proposed constant velocity c for electromagnetic waves. However the problem was, speed always had to be measured relative to something.
But what was this speed relative to in vacuum, in empty space, that is? That remained an unanswered question. Recalling his mental experiment of the railway carriage traveling at a speed of v and the passenger moving inside with a velocity w, Einstein tried to do 'thought experiments' by replacing the man (with velocity w) with a ray of light (with constant velocity c).
He found that it becomes incompatible with the Galilean relativity unless he considers the velocity of light same relative to the railway carriage and the railway station at the same time. By this time, it became clear to Einstein that the speed of light must be independent of the speed of the observer as well as of the speed of the source of the light. That would also mean that everyone in the universe, no matter how fast they were moving, would always observe the speed of light as constant c.
That goes against all normal Newtonian logic, but that must be true as otherwise you cannot solve the problem.
Confident of his logic, he boldly proposed that the velocity of light c must be constant 'relative to everything'. They asked, what do you mean by 'relative to everything?'
He said, it means exactly that, it is 'relative to everything'; c is a true universal constant. And that assumption basically solved the whole problem. Because once we accept this hypothesis, and are willing to discard just about everything else to make sure it holds true, we can end up with 'special theory of relativity' without a whole lot of mathematics, that is, if we know what we are doing. And that is what Einstein did.
The year 1905 is known as the ‘Miracle Year’ of Einstein. That year he submitted his Doctorate thesis and 4 of his major papers which eventually altered the very fabric of modern physics. The paper dealing with the famous equation was his last paper, titled 'Does the Inertia of a Body Depend Upon its Energy Content?' The paper was submitted in September 1905 as a follow up paper of his 'Special Theory of Relativity' submitted earlier in June 1905.
It may be noted that Einstein did not actually formulate exactly the formula E=mc2 in his paper. He even did not use the term E for energy, he used term L instead. In the paper he stated that if a body gives off the energy L in the form of radiation, its mass diminishes by L/c2 and that the inertua of a body represents its energy content.
This is of course is another way of saying the same thing, and the equation E=mc2 can easily be deduced from Einstein's prophetic statement. Importantly, Einstein was the first to have correctly deduced the mass–energy equivalence formula for the entire universe. Instead of proof, he made the statement that the validity of the equation may be tested by experiments.
Nearly all previous authors thought that the energy that contributes to mass comes only from electromagnetic fields. It may be said that while others were trying to write papers based on their mathematical derivations, Einstein was trying to find a natural law for the universe. That is where his greatness lies.
In this proposal, we see that Einstein's solution to the problem was simple and at the same time very profound. More than a mathematical genius, it shows his courage of imagination and the purity of thought.
What may be the secret of his great success? When asked, he used to say, "I have no special talents. I am only passionately curious". While it shows his humility, it also show a truth about what his being passionately curious. He was indeed passionately curious about solving the problem.
He was not concerned about time. His chasing the riddle of light for ten years proves that. As we see, Einstein used imaginative 'thought experiments' and was working all by himself in isolation to other professional physicists. In this case, we may say that he could solve the problem because he already sensed the answer through his imagination.
He was just looking for the process that will give him the answer. And the process told him that in order to find the answer he was looking for, he must take the velocity of light c as a universal constant . Einstein himself often used to say that "Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution."
In his evolution of the mass and energy equivalence, we clearly see how this is true. While the knowledge was available to all the scientists, it was only Einstein who could solve the puzzle with his imagination. As we see, his hypothesis that the speed of light is constant relative to everything was evolved not out of intense mathematical analysis but it came out of his strength of imagination and his courage to think against the flow.
[End of Article about e=mc2]
___________________________________________________________________________
3 EVERYDAY INVENTIONS EINSTEIN MADE POSSIBLE
By the Thales Group
What did Albert Einstein invent?Albert Einstein was not an inventor in the sense of da Vinci, Bell, or Edison.
Yet, he is recognized as one of the greatest physicists of all time and a genius for many.
This talented and fiercely independent mathematician and thinker changed how we see the universe through his theories and vision of physics.
In November 1915, Albert Einstein gave a series of lectures on his general theory of relativity at the Royal Prussian Academy of Sciences in Berlin.
It was the culmination of years of work, beginning with four groundbreaking papers in 1905:
- On his quantum theory of light (that light is a particle or photon),
- On the existence of atoms (the Brownian movement);
- On his theory of special relativity (that length and time are not fixed and depend on the observer's frame of reference),
- E=MC2 (that energy is linked to mass and the speed of light) on the equation for which he is most famous). A tiny particle of matter can create a vast quantity of energy, the basis of nuclear power.
Just think about it.
- He published these papers when he was just 26.
- Science would never be the same.
- Ten years later, Einstein further shook the physics world by theorizing that space and time are dynamic and distorted, affecting how objects and light move.
- This supposition was his general theory of relativity - his unified description of gravity.
- (Find a plain English primer on his main theories here.)
Three major inventions derived from Einstein's discoveries But these theories weren't confined to the lab. Since Einstein gave his lectures, what impact have his discoveries had on our everyday lives in the century?
1. Satnavs and Google Maps:
It's hard to get lost because of GPS - it allows our satnavs (satellite navigation systems) and smartphone map apps to tell us the quickest route to the restaurant or the beach.
But if it weren't for Einstein's general theory of relativity, we wouldn't know to consider relativity's effects when synchronizing the network of Global Positioning System (GPS) satellites orbiting the Earth.
This fact means their data would be filled with errors, making GPS more or less useless.
Einstein's theory of relativity shows that gravity and motion can affect time.
In GPS, the satellites that locate places move fast and are far from Earth's gravity, causing time to pass faster than on the ground. This can lead to errors in GPS, but atomic clocks can accurately measure time despite the effects of relativity.
GPS is made reliable and accurate by using atomic clocks and adjusting for time differences.
2. Your phone's clock:
Most ISPs and mobile phone masts use GPS to set the time.
And with each GPS satellite containing several atomic clocks, your computer and mobile phone clocks are ultra-accurate.
Without that accuracy, you'd probably be late (or early) for every meeting.
There's more.
3. Lasers
- What makes a supermarket's doors open automatically as you approach?
- Why do home security systems alert you to the presence of an intruder?
- How do smoke alarms detect fires?
Lasers are crucial to all these inventions and more.
Einstein's 1916 discovery of the physical principle was responsible for light amplification by stimulating the emission of radiation (the long-winded way of saying laser) that made these devices possible.
These are just three examples - virtually no corner of science and technology hasn't experienced the Einstein effect, from supercomputers and supernovas to nuclear weapons and the Big Bang.
And in our ever-more-digital world, what happens in the lab is never far from everyday life.
In the video below, stay with us and discover some amazing facts about this genius.
Re-evaluating Mileva Marić's contributions to Einstein's work:
Albert Einstein's first wife was Mileva Marić.
They met while studying physics at the Polytechnic in Zurich, Switzerland, and married in 1903. Marić was also a physicist; evidence suggests she contributed significantly to Einstein's work. However, their marriage was tumultuous, and they eventually separated in 1914, with a divorce finalized in 1919.
The extent of Mileva Marić's contribution to Einstein's work is a matter of debate among historians of science.
Some evidence suggests that Marić collaborated with Einstein on his early papers and may have contributed to his theories of relativity.
For example, in the early 1900s, Einstein and Marić worked on a paper exploring the relationship between mass and energy. The document was written in Einstein's handwriting, but some researchers believe that Marić made significant contributions to the calculations and ideas presented in the paper.
There are also letters between Einstein and Marić that suggest they discussed physics and collaborated on other papers. In one letter, Einstein refers to "our work on relative motion," which some historians interpret as evidence of a joint project between the two.
However, there is also evidence that Marić's contributions to Einstein's work were overstated in some accounts. Some argue that the available evidence does not definitively prove that Marić made significant contributions to Einstein's theories of relativity.
Einstein's biography in a nutshell:
Albert Einstein was a German-born physicist and one of the most influential scientists of the 20th century. He was born in Ulm, Germany, in 1879, and his contributions to theoretical physics have revolutionized our understanding of the universe.
Albert Einstein's education:
He received his primary education at a Catholic elementary school in Munich and later attended the Luitpold Gymnasium, where he was given advanced schooling. After his family moved to Italy, he stayed in Munich to finish his education. Einstein struggled with the school's rote learning methods and eventually left to join his family.
Einstein furthered his education at the Argovian cantonal school in Aarau, Switzerland, and excelled, especially in physics and mathematics. He graduated from the Federal Polytechnic School in Zurich.
In 1933, due to persecution by the Nazi regime and as a Jew, Einstein emigrated to the United States and renounced his German citizenship. He later became a naturalized US citizen in 1940.
Einstein passed away on April 18, 1955, at 76, due to complications related to an abdominal aortic aneurysm (Princeton, NJ, USA).
Einstein's legacy extends far beyond his scientific achievements. He was also a passionate advocate for peace and civil rights, using his platform to promote social justice causes and raise awareness about issues affecting humanity.
Einstein was also a skilled violinist and a prolific writer.
He published over 300 scientific papers and over 150 non-scientific works during his lifetime.
His work has profoundly impacted modern physics and influenced countless scientists, engineers, and thinkers.
So, if you're wondering, "What is Albert Einstein famous for?" it's his immense contributions to the field of physics and his theory of relativity which fundamentally changed our understanding of the universe.
Let's discover Albert Einstein: 22 surprising facts about Him:
What did Albert Einstein invent?Albert Einstein was not an inventor in the sense of da Vinci, Bell, or Edison.
Yet, he is recognized as one of the greatest physicists of all time and a genius for many.
This talented and fiercely independent mathematician and thinker changed how we see the universe through his theories and vision of physics.
In November 1915, Albert Einstein gave a series of lectures on his general theory of relativity at the Royal Prussian Academy of Sciences in Berlin.
It was the culmination of years of work, beginning with four groundbreaking papers in 1905:
- On his quantum theory of light (that light is a particle or photon),
- On the existence of atoms (the Brownian movement);
- On his theory of special relativity (that length and time are not fixed and depend on the observer's frame of reference),
- E=MC2 (that energy is linked to mass and the speed of light) on the equation for which he is most famous). A tiny particle of matter can create a vast quantity of energy, the basis of nuclear power.
Just think about it:
He published these papers when he was just 26.
Science would never be the same.
Ten years later, Einstein further shook the physics world by theorizing that space and time are dynamic and distorted, affecting how objects and light move.
This supposition was his general theory of relativity - his unified description of gravity.
(Find a plain English primer on his main theories here.)
Three major inventions derived from Einstein's discoveries But these theories weren't confined to the lab.
Since Einstein gave his lectures, what impact have his discoveries had on our everyday lives in the century?
1. Satnavs and Google Maps:
It's hard to get lost because of GPS - it allows our satnavs (satellite navigation systems) and smartphone map apps to tell us the quickest route to the restaurant or the beach.
But if it weren't for Einstein's general theory of relativity, we wouldn't know to consider relativity's effects when synchronizing the network of Global Positioning System (GPS) satellites orbiting the Earth.
This fact means their data would be filled with errors, making GPS more or less useless.
Einstein's theory of relativity shows that gravity and motion can affect time.
In GPS, the satellites that locate places move fast and are far from Earth's gravity, causing time to pass faster than on the ground. This can lead to errors in GPS, but atomic clocks can accurately measure time despite the effects of relativity.
GPS is made reliable and accurate by using atomic clocks and adjusting for time differences.
2. Your phone's clock:
Most ISPs and mobile phone masts use GPS to set the time. And with each GPS satellite containing several atomic clocks, your computer and mobile phone clocks are ultra-accurate.
Without that accuracy, you'd probably be late (or early) for every meeting.
There's more:
3. Lasers:
- What makes a supermarket's doors open automatically as you approach?
- Why do home security systems alert you to the presence of an intruder?
- How do smoke alarms detect fires?
Lasers are crucial to all these inventions and more.
Einstein's 1916 discovery of the physical principle was responsible for light amplification by stimulating the emission of radiation (the long-winded way of saying laser) that made these devices possible.
These are just three examples - virtually no corner of science and technology hasn't experienced the Einstein effect, from supercomputers and supernovas to nuclear weapons and the Big Bang.
And in our ever-more-digital world, what happens in the lab is never far from everyday life.
In the video below, stay with us and discover some amazing facts about this genius.
Re-evaluating Mileva Marić's contributions to Einstein's work:
Albert Einstein's first wife was Mileva Marić.
They met while studying physics at the Polytechnic in Zurich, Switzerland, and married in 1903. Marić was also a physicist; evidence suggests she contributed significantly to Einstein's work. However, their marriage was tumultuous, and they eventually separated in 1914, with a divorce finalized in 1919.
The extent of Mileva Marić's contribution to Einstein's work is a matter of debate among historians of science.
Some evidence suggests that Marić collaborated with Einstein on his early papers and may have contributed to his theories of relativity.
For example, in the early 1900s, Einstein and Marić worked on a paper exploring the relationship between mass and energy. The document was written in Einstein's handwriting, but some researchers believe that Marić made significant contributions to the calculations and ideas presented in the paper.
There are also letters between Einstein and Marić that suggest they discussed physics and collaborated on other papers. In one letter, Einstein refers to "our work on relative motion," which some historians interpret as evidence of a joint project between the two.
However, there is also evidence that Marić's contributions to Einstein's work were overstated in some accounts. Some argue that the available evidence does not definitively prove that Marić made significant contributions to Einstein's theories of relativity.
Einstein's biography in a nutshell:
Albert Einstein was a German-born physicist and one of the most influential scientists of the 20th century. He was born in Ulm, Germany, in 1879, and his contributions to theoretical physics have revolutionized our understanding of the universe.
Albert Einstein's education:
He received his primary education at a Catholic elementary school in Munich and later attended the Luitpold Gymnasium, where he was given advanced schooling. After his family moved to Italy, he stayed in Munich to finish his education. Einstein struggled with the school's rote learning methods and eventually left to join his family.
Einstein furthered his education at the Argovian cantonal school in Aarau, Switzerland, and excelled, especially in physics and mathematics. He graduated from the Federal Polytechnic School in Zurich.
In 1933, due to persecution by the Nazi regime and as a Jew, Einstein emigrated to the United States and renounced his German citizenship. He later became a naturalized US citizen in 1940.
Einstein passed away on April 18, 1955, at 76, due to complications related to an abdominal aortic aneurysm (Princeton, NJ, USA).
Einstein's legacy extends far beyond his scientific achievements.
- He was also a passionate advocate for peace and civil rights, using his platform to promote social justice causes and raise awareness about issues affecting humanity.
- Einstein was also a skilled violinist and a prolific writer.
- He published over 300 scientific papers and over 150 non-scientific works during his lifetime.
- His work has profoundly impacted modern physics and influenced countless scientists, engineers, and thinkers.
So, if you're wondering, "What is Albert Einstein famous for?" it's his immense contributions to the field of physics and his theory of relativity which fundamentally changed our understanding of the universe.
[End of Article #2]
___________________________________________________________________________
Albert Einstein (Wikipedia)
Albert Einstein (German: 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who is widely held to be one of the greatest and most influential scientists of all time.
Best known for developing the theory of relativity, Einstein also made important contributions to quantum mechanics, and was thus a central figure in the revolutionary reshaping of the scientific understanding of nature that modern physics accomplished in the first decades of the twentieth century.
His mass–energy equivalence formula E = mc2, which arises from relativity theory, has been called "the world's most famous equation". He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the development of quantum theory.
His work is also known for its influence on the philosophy of science/ In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World, Einstein was ranked the greatest physicist of all time. His intellectual achievements and originality have made the word Einstein broadly synonymous with genius.
Born in the German Empire, Einstein moved to Switzerland in 1895, forsaking his German citizenship (as a subject of the Kingdom of Württemberg) the following year. In 1897, at the age of seventeen, he enrolled in the mathematics and physics teaching diploma program at the Swiss Federal polytechnic school in Zürich, graduating in 1900. In 1901, he acquired Swiss citizenship, which he kept for the rest of his life.
In 1903, he secured a permanent position at the Swiss Patent Office in Bern. In 1905, he submitted a successful PhD dissertation to the University of Zurich. In 1914, he moved to Berlin in order to join the Prussian Academy of Sciences and the Humboldt University of Berlin.
In 1917, he became director of the Kaiser Wilhelm Institute for Physics; he also became a German citizen again, this time as a subject of the Kingdom of Prussia. In 1933, while he was visiting the United States, Adolf Hitler came to power in Germany.
Horrified by the Nazi "war of extermination" against his fellow Jews, Einstein decided to remain in the US, and was granted American citizenship in 1940.
On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential German nuclear weapons program and recommending that the US begin similar research. Einstein supported the Allies but generally viewed the idea of nuclear weapons with great dismay.
In 1905, a year sometimes described as his annus mirabilis (miracle year), Einstein published four groundbreaking papers. These outlined a theory of the photoelectric effect, explained Brownian motion, introduced his special theory of relativity—a theory which addressed the inability of classical mechanics to account satisfactorily for the behavior of the electromagnetic field—and demonstrated that if the special theory is correct, mass and energy are equivalent to each other.
In 1915, he proposed a general theory of relativity that extended his system of mechanics to incorporate gravitation. A cosmological paper that he published the following year laid out the implications of general relativity for the modeling of the structure and evolution of the universe as a whole.
The middle part of his career also saw him making important contributions to statistical mechanics and quantum theory. Especially notable was his work on the quantum physics of radiation, in which light consists of particles, subsequently called photons.
For much of the last phase of his academic life, Einstein worked on two endeavors that proved ultimately unsuccessful.
- He advocated against quantum theory's introduction of fundamental randomness into science's picture of the world, objecting that "God does not play dice".
- He attempted to devise a unified field theory by generalizing his geometric theory of gravitation to include electromagnetism too. As a result, he became increasingly isolated from the mainstream of modern physics.
Life and career:
Childhood, youth and education:
See also: Einstein family
Albert Einstein was born in Ulm, in the Kingdom of Württemberg in the German Empire, on 14 March 1879. His parents, secular Ashkenazi Jews, were Hermann Einstein, a salesman and engineer, and Pauline Koch.
In 1880, the family moved to Munich's borough of Ludwigsvorstadt-Isarvorstadt, where Einstein's father and his uncle Jakob founded Elektrotechnische Fabrik J. Einstein & Cie, a company that manufactured electrical equipment based on direct current.
Albert attended a Catholic elementary school in Munich from the age of five. When he was eight, he was transferred to the Luitpold-Gymnasium (now known as the Albert-Einstein-Gymnasium [de]) where he received advanced primary and then secondary school education.
In 1894, Hermann and Jakob's company tendered for a contract to install electric lighting in Munich, but without success—they lacked the capital that would have been required to update their technology from direct current to the more efficient, alternating current alternative.
The failure of their bid forced them to sell their Munich factory and search for new opportunities elsewhere. The Einstein family moved to Italy, first to Milan and a few months later to Pavia, where they settled in Palazzo Cornazzani. Einstein, then fifteen, stayed behind in Munich in order to finish his schooling.
His father wanted him to study electrical engineering, but he was a fractious pupil who found the Gymnasium's regimen and teaching methods far from congenial. He later wrote that the school's policy of strict rote learning was harmful to creativity.
At the end of December 1894, a letter from a doctor persuaded the Luitpold's authorities to release him from its care, and he joined his family in Pavia. While in Italy as a teenager, he wrote an essay entitled "On the Investigation of the State of the Ether in a Magnetic Field".
Einstein excelled at physics and mathematics from an early age, and soon acquired the mathematical expertise normally only found in a child several years his senior. He began teaching himself algebra, calculus and Euclidean geometry when he was twelve; he made such rapid progress that he discovered an original proof of the Pythagorean theorem before his thirteenth birthday.
A family tutor, Max Talmud, said that only a short time after he had given the twelve year old Einstein a geometry textbook, the boy "had worked through the whole book. He thereupon devoted himself to higher mathematics ... Soon the flight of his mathematical genius was so high I could not follow."
Einstein recorded that he had "mastered integral and differential calculus" while still just fourteen. His love of algebra and geometry was so great that at twelve, he was already confident that nature could be understood as a "mathematical structure".
At thirteen, when his range of enthusiasms had broadened to include music and philosophy, Einstein was introduced to Kant's Critique of Pure Reason. Kant became his favorite philosopher; according to his tutor, "At the time he was still a child, only thirteen years old, yet Kant's works, incomprehensible to ordinary mortals, seemed to be clear to him."
In 1895, at the age of sixteen, Einstein sat the entrance examination for the Federal polytechnic school (later the Eidgenössische Technische Hochschule, ETH) in Zürich, Switzerland. He failed to reach the required standard in the general part of the test, but performed with distinction in physics and mathematics.
On the advice of the polytechnic's principal, he completed his secondary education at the Argovian cantonal school (a gymnasium) in Aarau, Switzerland, graduating in 1896.
While lodging in Aarau with the family of Jost Winteler, he fell in love with Winteler's daughter, Marie. (His sister, Maja, later married Winteler's son Paul.)
In January 1896, with his father's approval, Einstein renounced his citizenship of the German Kingdom of Württemberg in order to avoid conscription into military service.
The Matura (graduation for the successful completion of higher secondary schooling) awarded to him in the September of that year acknowledged him to have performed well across most of the curriculum, allotting him a top grade of 6 for history, physics, algebra, geometry, and descriptive geometry.
At seventeen, he enrolled in the four-year mathematics and physics teaching diploma program at the Federal polytechnic school. Marie Winteler, a year older than him, took up a teaching post in Olsberg, Switzerland.
The five other polytechnic school freshmen following the same course as Einstein included just one woman, a twenty year old Serbian, Mileva Marić. Over the next few years, the pair spent many hours discussing their shared interests and learning about topics in physics that the polytechnic school's lectures did not cover.
In his letters to Marić, Einstein confessed that exploring science with her by his side was much more enjoyable than reading a textbook in solitude. Eventually the two students became not only friends but also lovers.
Historians of physics are divided on the question of the extent to which Marić contributed to the insights of Einstein's annus mirabilis publications. There is at least some evidence that he was influenced by her scientific ideas, but there are scholars who doubt whether her impact on his thought was of any great significance at all.
Marriages, relationships and children:
Correspondence between Einstein and Marić, discovered and published in 1987, revealed that in early 1902, while Marić was visiting her parents in Novi Sad, she gave birth to a daughter, Lieserl. When Marić returned to Switzerland it was without the child, whose fate is uncertain.
A letter of Einstein's that he wrote in September 1903 suggests that the girl was either given up for adoption or died of scarlet fever in infancy.
Einstein and Marić married in January 1903. In May 1904, their son Hans Albert was born in Bern, Switzerland. Their son Eduard was born in Zürich in July 1910. In letters that Einstein wrote to Marie Winteler in the months before Eduard's arrival, he described his love for his wife as "misguided" and mourned the "missed life" that he imagined he would have enjoyed if he had married Winteler instead: "I think of you in heartfelt love every spare minute and am so unhappy as only a man can be."
In 1912, Einstein entered into a relationship with Elsa Löwenthal, who was both his first cousin on his mother's side and his second cousin on his father's.
When Marić learned of his infidelity soon after moving to Berlin with him in April 1914, she returned to Zürich, taking Hans Albert and Eduard with her. Einstein and Marić were granted a divorce on 14 February 1919 on the grounds of having lived apart for five years.
As part of the divorce settlement, Einstein agreed that if he were to win a Nobel Prize, he would give the money that he received to Marić; she had to wait only two years before her foresight in extracting this promise from him was rewarded.
Einstein married Löwenthal in 1919. In 1923, he began a relationship with a secretary named Betty Neumann, the niece of his close friend Hans Mühsam. Löwenthal nevertheless remained loyal to him, accompanying him when he emigrated to the United States in 1933.
In 1935, she was diagnosed with heart and kidney problems. She died in December 1936.
A volume of Einstein's letters released by Hebrew University of Jerusalem in 2006 added further names to the catalog of women with whom he was romantically involved. They included:
- Margarete Lebach (a blonde Austrian),
- Estella Katzenellenbogen (the rich owner of a florist business),
- Toni Mendel (a wealthy Jewish widow)
- and Ethel Michanowski (a Berlin socialite), with whom he spent time and from whom he accepted gifts while married to Löwenthal.
After being widowed, Einstein was briefly in a relationship with Margarita Konenkova, thought by some to be a Russian spy; her husband, the Russian sculptor Sergei Konenkov, created the bronze bust of Einstein at the Institute for Advanced Study at Princeton.
Following an episode of acute mental illness at about the age of twenty, Einstein's son Eduard was diagnosed with schizophrenia. He spent the remainder of his life either in the care of his mother or in temporary confinement in an asylum. After her death, he was committed permanently to Burghölzli, the Psychiatric University Hospital in Zürich.
1902–1909: Assistant at the Swiss Patent Office:
Einstein graduated from the Federal polytechnic school in 1900, duly certified as competent to teach mathematics and physics. His successful acquisition of Swiss citizenship in February 1901 was not followed by the usual sequel of conscription; the Swiss authorities deemed him medically unfit for military service.
He found that Swiss schools too appeared to have no use for him, failing to offer him a teaching position despite the almost two years that he spent applying for one. Eventually it was with the help of Marcel Grossmann's father that he secured a post in Bern at the Swiss Patent Office, as an assistant examiner – level III.
Patent applications that landed on Einstein's desk for his evaluation included ideas for a gravel sorter and an electric typewriter. His employers were pleased enough with his work to make his position permanent in 1903, although they did not think that he should be promoted until he had "fully mastered machine technology". It is conceivable that his labors at the patent office had a bearing on his development of his special theory of relativity.
He arrived at his revolutionary ideas about space, time and light through thought experiments about the transmission of signals and the synchronization of clocks, matters which also figured in some of the inventions submitted to him for assessment.
In 1902, Einstein and some friends whom he had met in Bern formed a group that held regular meetings to discuss science and philosophy. Their choice of a name for their club, the Olympia Academy, was an ironic comment upon its far from Olympian status.
Sometimes they were joined by Marić, who limited her participation in their proceedings to careful listening.
The thinkers whose works they reflected upon included Henri Poincaré, Ernst Mach and David Hume, all of whom significantly influenced Einstein's own subsequent ideas and beliefs.
1900–1905: First scientific papers
Einstein's first paper, "Folgerungen aus den Capillaritätserscheinungen" ("Conclusions drawn from the phenomena of capillarity"), in which he proposed a model of intermolecular attraction that he afterwards disavowed as worthless, was published in the journal Annalen der Physik in 1900.
His 24-page doctoral dissertation also addressed a topic in molecular physics. Titled "Eine neue Bestimmung der Moleküldimensionen" ("A New Determination of Molecular Dimensions") and dedicated to his friend Marcel Grossman, it was completed on 30 April 1905 and approved by Professor Alfred Kleiner of the University of Zurich three months later.
(Einstein was formally awarded his PhD on 15 January 1906.)
Four other pieces of work that Einstein completed in 1905--his famous papers on the photoelectric effect, Brownian motion, his special theory of relativity and the equivalence of mass and energy—have led to the year's being celebrated as an annus mirabilis for physics almost as wonderful as 1666 (the year in which Isaac Newton experienced his greatest epiphanies). The publications deeply impressed Einstein's contemporaries.
1908–1933: Early academic career:
Einstein's sabbatical as a civil servant approached its end in 1908, when he secured a junior teaching position at the University of Bern.
In 1909, a lecture on relativistic electrodynamics that he gave at the University of Zurich, much admired by Alfred Kleiner, led to Zürich's luring him away from Bern with a newly created associate professorship.
Promotion to a full professorship followed in April 1911, when he accepted a chair at the German Charles-Ferdinand University in Prague, a move which required him to become an Austrian citizen of the Austro-Hungarian Empire. His time in Prague saw him producing eleven research papers.
In July 1912, he returned to his alma mater, the ETH Zurich, to take up a chair in theoretical physics. His teaching activities there centred on thermodynamics and analytical mechanics, and his research interests included the molecular theory of heat, continuum mechanics and the development of a relativistic theory of gravitation.
In his work on the latter topic, he was assisted by his friend, Marcel Grossmann, whose knowledge of the kind of mathematics required was greater than his own.
In the spring of 1913, two German visitors, Max Planck and Walther Nernst, called upon Einstein in Zürich in the hope of persuading him to relocate to Berlin. They offered him membership of the Prussian Academy of Sciences, the directorship of the planned Kaiser Wilhelm Institute for Physics and a chair at the Humboldt University of Berlin that would allow him to pursue his research supported by a professorial salary but with no teaching duties to burden him.
Their invitation was all the more appealing to him because Berlin happened to be the home of his latest girlfriend, Elsa Löwenthal. He duly joined the Academy on 24 July 1913, and moved into an apartment in the Berlin district of Dahlem on 1 April 1914. He was installed in his Humboldt University position shortly thereafter.
The outbreak of the First World War in July 1914 marked the beginning of Einstein's gradual estrangement from the nation of his birth.
When the "Manifesto of the Ninety-Three" was published in October 1914—a document signed by a host of prominent German thinkers that justified Germany's belligerence—Einstein was one of the few German intellectuals to distance himself from it and sign the alternative, eirenic "Manifesto to the Europeans" instead.
But this expression of his doubts about German policy did not prevent him from being elected to a two-year term as president of the German Physical Society in 1916. And when the Kaiser Wilhelm Institute for Physics opened its doors the following year—its foundation delayed because of the war—Einstein was appointed its first director, just as Planck and Nernst had promised.
Einstein was elected a Foreign Member of the Royal Netherlands Academy of Arts and Sciences in 1920, and a Foreign Member of the Royal Society in 1921. In 1922, he was awarded the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect".
At this point some physicists still regarded the general theory of relativity sceptically, and the Nobel citation displayed a degree of doubt even about the work on photoelectricity that it acknowledged: it did not assent to Einstein's notion of the particulate nature of light, which only won over the entire scientific community when S. N. Bose derived the Planck spectrum in 1924.
That same year, Einstein was elected an International Honorary Member of the American Academy of Arts and Sciences. Britain's closest equivalent of the Nobel award, the Royal Society's Copley Medal, was not hung around Einstein's neck until 1925. He was elected an International Member of the American Philosophical Society in 1930.
Einstein resigned from the Prussian Academy in March 1933. His accomplishments in Berlin had included the completion of the general theory of relativity, proving the Einstein–de Haas effect, contributing to the quantum theory of radiation, and the development of Bose–Einstein statistics.
1919: Putting general relativity to the test
In 1907, Einstein reached a milestone on his long journey from his special theory of relativity to a new idea of gravitation with the formulation of his equivalence principle, which asserts that an observer in an infinitesimally small box falling freely in a gravitational field would be unable to find any evidence that the field exists.
In 1911, he used the principle to estimate the amount by which a ray of light from a distant star would be bent by the gravitational pull of the Sun as it passed close to the Sun's photosphere (that is, the Sun's apparent surface).
He reworked his calculation in 1913, having now found a way to model gravitation with the Riemann curvature tensor of a non-Euclidean four-dimensional spacetime.
By the fall of 1915, his reimagining of the mathematics of gravitation in terms of Riemannian geometry was complete, and he applied his new theory not just to the behavior of the Sun as a gravitational lens but also to another astronomical phenomenon, the precession of the perihelion of Mercury (a slow drift in the point in Mercury's elliptical orbit at which it approaches the Sun most closely).
A total eclipse of the Sun that took place on 29 May 1919 provided an opportunity to put his theory of gravitational lensing to the test, and observations performed by Sir Arthur Eddington yielded results that were consistent with his calculations.
Eddington's work was reported at length in newspapers around the world. On 7 November 1919, for example, the leading British newspaper, The Times, printed a banner headline that read: "Revolution in Science – New Theory of the Universe – Newtonian Ideas Overthrown".
1921–1923: Coming to terms with fame
With Eddington's eclipse observations widely reported not just in academic journals but by the popular press as well, Einstein became "perhaps the world's first celebrity scientist", a genius who had shattered a paradigm that had been basic to physicists' understanding of the universe since the seventeenth century.
Einstein began his new life as an intellectual icon in America, where he arrived on 2 April 1921. He was welcomed to New York City by Mayor John Francis Hylan, and then spent three weeks giving lectures and attending receptions.
He spoke several times at Columbia University and Princeton, and in Washington, he visited the White House with representatives of the National Academy of Sciences. He returned to Europe via London, where he was the guest of the philosopher and statesman Viscount Haldane.
He used his time in the British capital to meet several people prominent in British scientific, political or intellectual life, and to deliver a lecture at King's College. In July 1921, he published an essay, "My First Impression of the U.S.A.", in which he sought to sketch the American character, much as had Alexis de Tocqueville in Democracy in America (1835).
He wrote of his transatlantic hosts in highly approving terms: "What strikes a visitor is the joyous, positive attitude to life ... The American is friendly, self-confident, optimistic, and without envy."
In 1922, Einstein's travels were to the old world rather than the new. He devoted six months to a tour of Asia that saw him speaking in Japan, Singapore and Sri Lanka (then known as Ceylon).
After his first public lecture in Tokyo, he met Emperor Yoshihito and his wife at the Imperial Palace, with thousands of spectators thronging the streets in the hope of catching a glimpse of him. (In a letter to his sons, he wrote that Japanese people seemed to him to be generally modest, intelligent and considerate, and to have a true appreciation of art. But his picture of them in his diary was less flattering: "[the] intellectual needs of this nation seem to be weaker than their artistic ones – natural disposition?" His journal also contains views of China and India which were uncomplimentary.
Of Chinese people, he wrote that "even the children are spiritless and look obtuse... It would be a pity if these Chinese supplant all other races. For the likes of us the mere thought is unspeakably dreary".)
He was greeted with even greater enthusiasm on the last leg of his tour, in which he spent twelve days in Mandatory Palestine, newly entrusted to British rule by the League of Nations in the aftermath of the First World War. Sir Herbert Samuel, the British High Commissioner, welcomed him with a degree of ceremony normally only accorded to a visiting head of state, including a cannon salute.
One reception held in his honor was stormed by people determined to hear him speak: he told them that he was happy that Jews were beginning to be recognized as a force in the world.
Einstein's decision to tour the eastern hemisphere in 1922 meant that he was unable to go to Stockholm in the December of that year to participate in the Nobel prize ceremony. His place at the traditional Nobel banquet was taken by a German diplomat, who gave a speech praising him not only as a physicist but also as a campaigner for peace.
A two week visit to Spain that he undertook in 1923 saw him collecting another award, a membership of the Spanish Academy of Sciences signified by a diploma handed to him by King Alfonso XIII. (His Spanish trip also gave him a chance to meet a fellow Nobel laureate, the neuroanatomist Santiago Ramón y Cajal.)
1922–1932: Serving the League of Nations
Einstein at a session of the International Committee on Intellectual Cooperation (League of Nations) of which he was a member from 1922 to 1932. From 1922 until 1932, with the exception of a few months in 1923 and 1924, Einstein was a member of the Geneva-based International Committee on Intellectual Cooperation of the League of Nations, a group set up by the League to encourage scientists, artists, scholars, teachers and other people engaged in the life of the mind to work more closely with their counterparts in other countries.
He was appointed as a German delegate rather than as a representative of Switzerland because of the machinations of two Catholic activists, Oskar Halecki and Giuseppe Motta.
By persuading Secretary General Eric Drummond to deny Einstein the place on the committee reserved for a Swiss thinker, they created an opening for Gonzague de Reynold, who used his League of Nations position as a platform from which to promote traditional Catholic doctrine.
Einstein's former physics professor Hendrik Lorentz and the Polish chemist Marie Curie were also members of the committee.
1925: Touring South America:
In March and April 1925, Einstein and his wife visited South America, where they spent about a week in Brazil, a week in Uruguay and a month in Argentina. Their tour was suggested by Jorge Duclout (1856–1927) and Mauricio Nirenstein (1877–1935) with the support of several Argentine scholars, including Julio Rey Pastor, Jakob Laub, and Leopoldo Lugones. and was financed primarily by the Council of the University of Buenos Aires and the Asociación Hebraica Argentina (Argentine Hebraic Association) with a smaller contribution from the Argentine-Germanic Cultural Institution.
1930–1931: Touring the US:
In December 1930, Einstein began another significant sojourn in the United States, drawn back to the US by the offer of a two month research fellowship at the California Institute of Technology.
Caltech supported him in his wish that he should not be exposed to quite as much attention from the media as he had experienced when visiting the US in 1921, and he therefore declined all the invitations to receive prizes or make speeches that his admirers poured down upon him. But he remained willing to allow his fans at least some of the time with him that they requested.
After arriving in New York City, Einstein was taken to various places and events, including Chinatown, a lunch with the editors of The New York Times, and a performance of Carmen at the Metropolitan Opera, where he was cheered by the audience on his arrival.
During the days following, he was given the keys to the city by Mayor Jimmy Walker and met Nicholas Murray Butler, the president of Columbia University, who described Einstein as "the ruling monarch of the mind".
Harry Emerson Fosdick, pastor at New York's Riverside Church, gave Einstein a tour of the church and showed him a full-size statue that the church made of Einstein, standing at the entrance. Also during his stay in New York, he joined a crowd of 15,000 people at Madison Square Garden during a Hanukkah celebration.
Einstein next traveled to California, where he met Caltech president and Nobel laureate Robert A. Millikan. His friendship with Millikan was "awkward", as Millikan "had a penchant for patriotic militarism", where Einstein was a pronounced pacifist.
During an address to Caltech's students, Einstein noted that science was often inclined to do more harm than good.
This aversion to war also led Einstein to befriend author Upton Sinclair and film star Charlie Chaplin, both noted for their pacifism. Carl Laemmle, head of Universal Studios, gave Einstein a tour of his studio and introduced him to Chaplin.
They had an instant rapport, with Chaplin inviting Einstein and his wife, Elsa, to his home for dinner. Chaplin said Einstein's outward persona, calm and gentle, seemed to conceal a "highly emotional temperament", from which came his "extraordinary intellectual energy".
Chaplin's film, City Lights, was to premiere a few days later in Hollywood, and Chaplin invited Einstein and Elsa to join him as his special guests. Walter Isaacson, Einstein's biographer, described this as "one of the most memorable scenes in the new era of celebrity".
Chaplin visited Einstein at his home on a later trip to Berlin and recalled his "modest little flat" and the piano at which he had begun writing his theory. Chaplin speculated that it was "possibly used as kindling wood by the Nazis".
1933: Emigration to the US
In February 1933, while on a visit to the United States, Einstein knew he could not return to Germany with the rise to power of the Nazis under Germany's new chancellor, Adolf Hitler.
While at American universities in early 1933, he undertook his third two-month visiting professorship at the California Institute of Technology in Pasadena. In February and March 1933, the Gestapo repeatedly raided his family's apartment in Berlin.
He and his wife Elsa returned to Europe in March, and during the trip, they learned that the German Reichstag had passed the Enabling Act on 23 March, transforming Hitler's government into a de facto legal dictatorship, and that they would not be able to proceed to Berlin.
Later on, they heard that their cottage had been raided by the Nazis and Einstein's personal sailboat confiscated. Upon landing in Antwerp, Belgium on 28 March, Einstein immediately went to the German consulate and surrendered his passport, formally renouncing his German citizenship. The Nazis later sold his boat and converted his cottage into a Hitler Youth camp.
Refugee status
Landing card for Einstein's 26 May 1933 arrival in Dover, England from Ostend, Belgium, enroute to Oxford.In April 1933, Einstein discovered that the new German government had passed laws barring Jews from holding any official positions, including teaching at universities.
Historian Gerald Holton describes how, with "virtually no audible protest being raised by their colleagues", thousands of Jewish scientists were suddenly forced to give up their university positions and their names were removed from the rolls of institutions where they were employed.
A month later, Einstein's works were among those targeted by the German Student Union in the Nazi book burnings, with Nazi propaganda minister Joseph Goebbels proclaiming, "Jewish intellectualism is dead." One German magazine included him in a list of enemies of the German regime with the phrase, "not yet hanged", offering a $5,000 bounty on his head.
In a subsequent letter to physicist and friend Max Born, who had already emigrated from Germany to England, Einstein wrote, "... I must confess that the degree of their brutality and cowardice came as something of a surprise."
After moving to the US, he described the book burnings as a "spontaneous emotional outburst" by those who "shun popular enlightenment", and "more than anything else in the world, fear the influence of men of intellectual independence".
Einstein was now without a permanent home, unsure where he would live and work, and equally worried about the fate of countless other scientists still in Germany. Aided by the Academic Assistance Council, founded in April 1933 by British Liberal politician William Beveridge to help academics escape Nazi persecution, Einstein was able to leave Germany.
He rented a house in De Haan, Belgium, where he lived for a few months. In late July 1933, he visited England for about six weeks at the invitation of the British Member of Parliament Commander Oliver Locker-Lampson, who had become friends with him in the preceding years.
Locker-Lampson invited him to stay near his Cromer home in a secluded wooden cabin on Roughton Heath in the Parish of Roughton, Norfolk. To protect Einstein, Locker-Lampson had two bodyguards watch over him; a photo of them carrying shotguns and guarding Einstein was published in the Daily Herald on 24 July 1933.
Locker-Lampson took Einstein to meet Winston Churchill at his home, and later, Austen Chamberlain and former Prime Minister Lloyd George. Einstein asked them to help bring Jewish scientists out of Germany. British historian Martin Gilbert notes that Churchill responded immediately, and sent his friend, physicist Frederick Lindemann, to Germany to seek out Jewish scientists and place them in British universities.
Churchill later observed that as a result of Germany having driven the Jews out, they had lowered their "technical standards" and put the Allies' technology ahead of theirs.
Einstein later contacted leaders of other nations, including Turkey's Prime Minister, İsmet İnönü, to whom he wrote in September 1933 requesting placement of unemployed German-Jewish scientists. As a result of Einstein's letter, Jewish invitees to Turkey eventually totaled over "1,000 saved individuals".
Locker-Lampson also submitted a bill to parliament to extend British citizenship to Einstein, during which period Einstein made a number of public appearances describing the crisis brewing in Europe.
In one of his speeches he denounced Germany's treatment of Jews, while at the same time he introduced a bill promoting Jewish citizenship in Palestine, as they were being denied citizenship elsewhere. In his speech he described Einstein as a "citizen of the world" who should be offered a temporary shelter in the UK.
Both bills failed, however, and Einstein then accepted an earlier offer from the Institute for Advanced Study, in Princeton, New Jersey, US, to become a resident scholar.
Resident scholar at the Institute for Advanced Study
On 3 October 1933, Einstein delivered a speech on the importance of academic freedom before a packed audience at the Royal Albert Hall in London, with The Times reporting he was wildly cheered throughout. Four days later he returned to the US and took up a position at the Institute for Advanced Study, noted for having become a refuge for scientists fleeing Nazi Germany.
At the time, most American universities, including Harvard, Princeton and Yale, had minimal or no Jewish faculty or students, as a result of their Jewish quotas, which lasted until the late 1940s.
Einstein was still undecided on his future. He had offers from several European universities, including Christ Church, Oxford, where he stayed for three short periods between May 1931 and June 1933 and was offered a five-year research fellowship (called a "studentship" at Christ Church), but in 1935, he arrived at the decision to remain permanently in the United States and apply for citizenship.
Einstein's affiliation with the Institute for Advanced Study would last until his death in 1955. He was one of the four first selected (along with John von Neumann, Kurt Gödel, and Hermann Weyl) at the new Institute. He soon developed a close friendship with Gödel; the two would take long walks together discussing their work. Bruria Kaufman, his assistant, later became a physicist.
During this period, Einstein tried to develop a unified field theory and to refute the accepted interpretation of quantum physics, both unsuccessfully. He lived in Princeton at his home from 1935 onwards. The Albert Einstein House was made a National Historic Landmark in 1976.
World War II and the Manhattan Project
See also: Einstein–Szilárd letter
In 1939, a group of Hungarian scientists that included émigré physicist Leó Szilárd attempted to alert Washington to ongoing Nazi atomic bomb research.
The group's warnings were discounted. Einstein and Szilárd, along with other refugees such as Edward Teller and Eugene Wigner, "regarded it as their responsibility to alert Americans to the possibility that German scientists might win the race to build an atomic bomb, and to warn that Hitler would be more than willing to resort to such a weapon."
To make certain the US was aware of the danger, in July 1939, a few months before the beginning of World War II in Europe, Szilárd and Wigner visited Einstein to explain the possibility of atomic bombs, which Einstein, a pacifist, said he had never considered.
He was asked to lend his support by writing a letter, with Szilárd, to President Roosevelt, recommending the US pay attention and engage in its own nuclear weapons research.
The letter is believed to be "arguably the key stimulus for the U.S. adoption of serious investigations into nuclear weapons on the eve of the U.S. entry into World War II".
In addition to the letter, Einstein used his connections with the Belgian royal family and the Belgian queen mother to get access with a personal envoy to the White House's Oval Office. Some say that as a result of Einstein's letter and his meetings with Roosevelt, the US entered the "race" to develop the bomb, drawing on its "immense material, financial, and scientific resources" to initiate the Manhattan Project.
For Einstein, "war was a disease ... [and] he called for resistance to war." By signing the letter to Roosevelt, some argue he went against his pacifist principles. In 1954, a year before his death, Einstein said to his old friend, Linus Pauling, "I made one great mistake in my life—when I signed the letter to President Roosevelt recommending that atom bombs be made; but there was some justification—the danger that the Germans would make them ..."
In 1955, Einstein and ten other intellectuals and scientists, including British philosopher Bertrand Russell, signed a manifesto highlighting the danger of nuclear weapons.
In 1960 Einstein was included posthumously as a charter member of the World Academy of Art and Science (WAAS), an organization founded by distinguished scientists and intellectuals who committed themselves to the responsible and ethical advances of science, particularly in light of the development of nuclear weapons.
US citizenship
Einstein became an American citizen in 1940. Not long after settling into his career at the Institute for Advanced Study in Princeton, New Jersey, he expressed his appreciation of the meritocracy in American culture compared to Europe.
He recognized the "right of individuals to say and think what they pleased" without social barriers. As a result, individuals were encouraged, he said, to be more creative, a trait he valued from his early education.
Einstein joined the National Association for the Advancement of Colored People (NAACP) in Princeton, where he campaigned for the civil rights of African Americans. He considered racism America's "worst disease", seeing it as "handed down from one generation to the next".
As part of his involvement, he corresponded with civil rights activist W. E. B. Du Bois and was prepared to testify on his behalf during his trial as an alleged foreign agent in 1951. When Einstein offered to be a character witness for Du Bois, the judge decided to drop the case.
In 1946, Einstein visited Lincoln University in Pennsylvania, a historically black college, where he was awarded an honorary degree. Lincoln was the first university in the United States to grant college degrees to African Americans; alumni include Langston Hughes and Thurgood Marshall.
Einstein gave a speech about racism in America, adding, "I do not intend to be quiet about it." A resident of Princeton recalls that Einstein had once paid the college tuition for a black student. Einstein has said, "Being a Jew myself, perhaps I can understand and empathize with how black people feel as victims of discrimination".
Personal views:
Political views
Main article: Political views of Albert Einstein
Albert Einstein and Elsa Einstein arriving in New York in 1921. Accompanying them are Zionist leaders Chaim Weizmann (future president of Israel), Weizmann's wife Vera Weizmann, Menahem Ussishkin, and Ben-Zion Mossinson.
In 1918, Einstein was one of the signatories of the founding proclamation of the German Democratic Party, a liberal party. Later in his life, Einstein's political view was in favor of socialism and critical of capitalism, which he detailed in his essays such as "Why Socialism?".
His opinions on the Bolsheviks also changed with time. In 1925, he criticized them for not having a "well-regulated system of government" and called their rule a "regime of terror and a tragedy in human history".
He later adopted a more moderated view, criticizing their methods but praising them, which is shown by his 1929 remark on Vladimir Lenin: "In Lenin I honor a man, who in total sacrifice of his own person has committed his entire energy to realizing social justice. I do not find his methods advisable. One thing is certain, however: men like him are theguardians and renewers of mankind's conscience."
Einstein offered and was called on to give judgments and opinions on matters often unrelated to theoretical physics or mathematics. He strongly advocated the idea of a democratic global government that would check the power of nation-states in the framework of a world federation.
He wrote "I advocate world government because I am convinced that there is no other possible way of eliminating the most terrible danger in which man has ever found himself." The FBI created a secret dossier on Einstein in 1932; by the time of his death, it was 1,427 pages long.
Einstein was deeply impressed by Mahatma Gandhi, with whom he corresponded. He described Gandhi as "a role model for the generations to come".
The initial connection was established on 27 September 1931, when Wilfrid Israel took his Indian guest V. A. Sundaram to meet his friend Einstein at his summer home in the town of Caputh. Sundaram was Gandhi's disciple and special envoy, whom Wilfrid Israel met while visiting India and visiting the Indian leader's home in 1925.
During the visit, Einstein wrote a short letter to Gandhi that was delivered to him through his envoy, and Gandhi responded quickly with his own letter. Although in the end Einstein and Gandhi were unable to meet as they had hoped, the direct connection between them was established through Wilfrid Israel.
Relationship with Zionism
In 1947, Einstein was a figurehead leader in the establishment of the Hebrew University of Jerusalem, which opened in 1925. Earlier, in 1921, he was asked by the biochemist and president of the World Zionist Organization, Chaim Weizmann, to help raise funds for the planned university.
He made suggestions for the creation of an Institute of Agriculture, a Chemical Institute and an Institute of Microbiology in order to fight the various ongoing epidemics such as malaria, which he called an "evil" that was undermining a third of the country's development. He also promoted the establishment of an Oriental Studies Institute, to include language courses given in both Hebrew and Arabic.
Einstein was not a nationalist and opposed the creation of an independent Jewish state. He felt that the waves of arriving Jews of the Aliyah could live alongside existing Arabs in Palestine.
The state of Israel was established without his help in 1948; Einstein was limited to a marginal role in the Zionist movement. Upon the death of Israeli president Weizmann in November 1952, Prime Minister David Ben-Gurion offered Einstein the largely ceremonial position of President of Israel at the urging of Ezriel Carlebach.
The offer was presented by Israel's ambassador in Washington, Abba Eban, who explained that the offer "embodies the deepest respect which the Jewish people can repose in any of its sons". Einstein wrote that he was "deeply moved", but "at once saddened and ashamed" that he could not accept it.
Religious and philosophical views
Main article: Religious and philosophical views of Albert Einstein
Einstein expounded his spiritual outlook in a wide array of writings and interviews. He said he had sympathy for the impersonal pantheistic God of Baruch Spinoza's philosophy.
He did not believe in a personal god who concerns himself with fates and actions of human beings, a view which he described as naïve. He clarified, however, that "I am not an atheist", preferring to call himself an agnostic, or a "deeply religious nonbeliever".
When asked if he believed in an afterlife, Einstein replied, "No. And one life is enough for me."
Einstein was primarily affiliated with non-religious humanist and Ethical Culture groups in both the UK and US. He served on the advisory board of the First Humanist Society of New York, and was an honorary associate of the Rationalist Association, which publishes New Humanist in Britain.
For the 75th anniversary of the New York Society for Ethical Culture, he stated that the idea of Ethical Culture embodied his personal conception of what is most valuable and enduring in religious idealism. He observed, "Without 'ethical culture' there is no salvation for humanity."
In a German-language letter to philosopher Eric Gutkind, dated 3 January 1954, Einstein wrote: "The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honorable, but still primitive legends which are nevertheless pretty childish. No interpretation no matter how subtle can (for me) change this. ... For me the Jewish religion like all other religions is an incarnation of the most childish superstitions. And the Jewish people to whom I gladly belong and with whose mentality I have a deep affinity have no different quality for me than all other people. ... I cannot see anything 'chosen' about them.
Einstein had been sympathetic toward vegetarianism for a long time. In a letter in 1930 to Hermann Huth, vice-president of the German Vegetarian Federation (Deutsche Vegetarier-Bund), he wrote: "Although I have been prevented by outward circumstances from observing a strictly vegetarian diet, I have long been an adherent to the cause in principle. Besides agreeing with the aims of vegetarianism for aesthetic and moral reasons, it is my view that a vegetarian manner of living by its purely physical effect on the human temperament would most beneficially influence the lot of mankind.
He became a vegetarian himself only during the last part of his life. In March 1954 he wrote in a letter: "So I am living without fats, without meat, without fish, but am feeling quite well this way. It almost seems to me that man was not born to be a carnivore."
Love of music:
Einstein developed an appreciation for music at an early age. In his late journals he wrote:
If I were not a physicist, I would probably be a musician. I often think in music. I live my daydreams in music. I see my life in terms of music ... I get most joy in life out of music.
His mother played the piano reasonably well and wanted her son to learn the violin, not only to instill in him a love of music but also to help him assimilate into German culture.
According to conductor Leon Botstein, Einstein began playing when he was 5. However, he did not enjoy it at that age.
When he turned 13, he discovered the violin sonatas of Mozart, whereupon he became enamored of Mozart's compositions and studied music more willingly. Einstein taught himself to play without "ever practicing systematically". He said that "love is a better teacher than a sense of duty".
At the age of 17, he was heard by a school examiner in Aarau while playing Beethoven's violin sonatas. The examiner stated afterward that his playing was "remarkable and revealing of 'great insight'". What struck the examiner, writes Botstein, was that Einstein "displayed a deep love of the music, a quality that was and remains in short supply. Music possessed an unusual meaning for this student."
Music took on a pivotal and permanent role in Einstein's life from that period on. Although the idea of becoming a professional musician himself was not on his mind at any time, among those with whom Einstein played chamber music were a few professionals, including Kurt Appelbaum, and he performed for private audiences and friends.
Chamber music had also become a regular part of his social life while living in Bern, Zürich, and Berlin, where he played with Max Planck and his son, among others. He is sometimes erroneously credited as the editor of the 1937 edition of the Köchel catalog of Mozart's work; that edition was prepared by Alfred Einstein, who may have been a distant relation.
In 1931, while engaged in research at the California Institute of Technology, he visited the Zoellner family conservatory in Los Angeles, where he played some of Beethoven and Mozart's works with members of the Zoellner Quartet.
Near the end of his life, when the young Juilliard Quartet visited him in Princeton, he played his violin with them, and the quartet was "impressed by Einstein's level of coordination and intonation".
Death:
On 17 April 1955, Einstein experienced internal bleeding caused by the rupture of an abdominal aortic aneurysm, which had previously been reinforced surgically by Rudolph Nissen in 1948. He took the draft of a speech he was preparing for a television appearance commemorating the state of Israel's seventh anniversary with him to the hospital, but he did not live to complete it.
Einstein refused surgery, saying, "I want to go when I want. It is tasteless to prolong life artificially. I have done my share; it is time to go. I will do it elegantly." He died in the Princeton Hospital early the next morning at the age of 76, having continued to work until near the end.
During the autopsy, the pathologist Thomas Stoltz Harvey removed Einstein's brain for preservation without the permission of his family, in the hope that the neuroscience of the future would be able to discover what made Einstein so intelligent.
Einstein's remains were cremated in Trenton, New Jersey, and his ashes were scattered at an undisclosed location.
In a memorial lecture delivered on 13 December 1965 at UNESCO headquarters, nuclear physicist J. Robert Oppenheimer summarized his impression of Einstein as a person: "He was almost wholly without sophistication and wholly without worldliness ... There was always with him a wonderful purity at once childlike and profoundly stubborn."
Einstein bequeathed his personal archives, library, and intellectual assets to the Hebrew University of Jerusalem in Israel.
Scientific career:
Throughout his life, Einstein published hundreds of books and articles. He published more than 300 scientific papers and 150 non-scientific ones.
On 5 December 2014, universities and archives announced the release of Einstein's papers, comprising more than 30,000 unique documents. Einstein's intellectual achievements and originality have made the word "Einstein" synonymous with "genius".
In addition to the work he did by himself he also collaborated with other scientists on additional projects including the Bose–Einstein statistics, the Einstein refrigerator and others.
There is some evidence from Einstein's writings that he collaborated with his first wife, Mileva Marić. In 13 December 1900, a first article on capillarity signed only under his name was submitted. The decision to publish only under his name seems to have been mutual, but the exact reason is unknown.
1905 – Annus Mirabilis papers:
The Annus Mirabilis papers are four articles pertaining to the photoelectric effect (which gave rise to quantum theory), Brownian motion, the special theory of relativity, and E = mc2 that Einstein published in the Annalen der Physik scientific journal in 1905.
These four works contributed substantially to the foundation of modern physics and changed views on space, time, and matter. The four papers are::
Statistical mechanics
Thermodynamic fluctuations and statistical physics
Main articles below:
Einstein's first paper submitted in 1900 to Annalen der Physik was on capillary attraction. It was published in 1901 with the title "Folgerungen aus den Capillaritätserscheinungen", which translates as "Conclusions from the capillarity phenomena".
Two papers he published in 1902–1903 (thermodynamics) attempted to interpret atomic phenomena from a statistical point of view. These papers were the foundation for the 1905 paper on Brownian motion, which showed that Brownian movement can be construed as firm evidence that molecules exist. His research in 1903 and 1904 was mainly concerned with the effect of finite atomic size on diffusion phenomena.
Theory of critical opalescence
Main article: Critical opalescence
Einstein returned to the problem of thermodynamic fluctuations, giving a treatment of the density variations in a fluid at its critical point. Ordinarily the density fluctuations are controlled by the second derivative of the free energy with respect to the density.
At the critical point, this derivative is zero, leading to large fluctuations. The effect of density fluctuations is that light of all wavelengths is scattered, making the fluid look milky white.
Einstein relates this to Rayleigh scattering, which is what happens when the fluctuation size is much smaller than the wavelength, and which explains why the sky is blue. Einstein quantitatively derived critical opalescence from a treatment of density fluctuations, and demonstrated how both the effect and Rayleigh scattering originate from the atomistic constitution of matter.
Special relativity:
Main article: History of special relativity
Einstein's "Zur Elektrodynamik bewegter Körper" ("On the Electrodynamics of Moving Bodies") was received on 30 June 1905 and published 26 September of that same year. It reconciled conflicts between Maxwell's equations (the laws of electricity and magnetism) and the laws of Newtonian mechanics by introducing changes to the laws of mechanics.
Observationally, the effects of these changes are most apparent at high speeds (where objects are moving at speeds close to the speed of light). The theory developed in this paper later became known as Einstein's special theory of relativity.
This paper predicted that, when measured in the frame of a relatively moving observer, a clock carried by a moving body would appear to slow down, and the body itself would contract in its direction of motion. This paper also argued that the idea of a luminiferous aether—one of the leading theoretical entities in physics at the time—was superfluous.
In his paper on mass–energy equivalence, Einstein produced E = mc2 as a consequence of his special relativity equations. Einstein's 1905 work on relativity remained controversial for many years, but was accepted by leading physicists, starting with Max Planck.
Einstein originally framed special relativity in terms of kinematics (the study of moving bodies). In 1908, Hermann Minkowski reinterpreted special relativity in geometric terms as a theory of spacetime. Einstein adopted Minkowski's formalism in his 1915 general theory of relativity.
General relativity:
General relativity and the equivalence principle
Main article: History of general relativity
See also:
General relativity (GR) is a theory of gravitation that was developed by Einstein between 1907 and 1915. According to it, the observed gravitational attraction between masses results from the warping of spacetime by those masses.
General relativity has developed into an essential tool in modern astrophysics; it provides the foundation for the current understanding of black holes, regions of space where gravitational attraction is so strong that not even light can escape.
As Einstein later said, the reason for the development of general relativity was that the preference of inertial motions within special relativity was unsatisfactory, while a theory which from the outset prefers no state of motion (even accelerated ones) should appear more satisfactory.
Consequently, in 1907 he published an article on acceleration under special relativity. In that article titled "On the Relativity Principle and the Conclusions Drawn from It", he argued that free fall is really inertial motion, and that for a free-falling observer the rules of special relativity must apply. This argument is called the equivalence principle.
In the same article, Einstein also predicted the phenomena of:
In 1911, Einstein published another article "On the Influence of Gravitation on the Propagation of Light" expanding on the 1907 article, in which he estimated the amount of deflection of light by massive bodies. Thus, the theoretical prediction of general relativity could for the first time be tested experimentally.
Gravitational waves:
In 1916, Einstein predicted gravitational waves, ripples in the curvature of spacetime which propagate as waves, traveling outward from the source, transporting energy as gravitational radiation.
The existence of gravitational waves is possible under general relativity due to its Lorentz invariance which brings the concept of a finite speed of propagation of the physical interactions of gravity with it.
By contrast, gravitational waves cannot exist in the Newtonian theory of gravitation, which postulates that the physical interactions of gravity propagate at infinite speed.
The first, indirect, detection of gravitational waves came in the 1970s through observation of a pair of closely orbiting neutron stars, PSR B1913+16. The explanation for the decay in their orbital period was that they were emitting gravitational waves.
Einstein's prediction was confirmed on 11 February 2016, when researchers at LIGO published the first observation of gravitational waves, detected on Earth on 14 September 2015, nearly one hundred years after the prediction.
Hole argument and Entwurf theory:
While developing general relativity, Einstein became confused about the gauge invariance in the theory. He formulated an argument that led him to conclude that a general relativistic field theory is impossible. He gave up looking for fully generally covariant tensor equations and searched for equations that would be invariant under general linear transformations only.
In June 1913, the Entwurf ('draft') theory was the result of these investigations. As its name suggests, it was a sketch of a theory, less elegant and more difficult than general relativity, with the equations of motion supplemented by additional gauge fixing conditions. After more than two years of intensive work, Einstein realized that the hole argument was mistaken and abandoned the theory in November 1915.
Physical cosmology
Main article: Physical cosmology
In 1917, Einstein applied the general theory of relativity to the structure of the universe as a whole. He discovered that the general field equations predicted a universe that was dynamic, either contracting or expanding. As observational evidence for a dynamic universe was lacking at the time, Einstein introduced a new term, the cosmological constant, into the field equations, in order to allow the theory to predict a static universe.
The modified field equations predicted a static universe of closed curvature, in accordance with Einstein's understanding of Mach's principle in these years. This model became known as the Einstein World or Einstein's static universe.
Following the discovery of the recession of the galaxies by Edwin Hubble in 1929, Einstein abandoned his static model of the universe, and proposed two dynamic models of the cosmos, the Friedmann–Einstein universe of 1931 and the Einstein–de Sitter universe of 1932.
In each of these models, Einstein discarded the cosmological constant, claiming that it was "in any case theoretically unsatisfactory".
In many Einstein biographies, it is claimed that Einstein referred to the cosmological constant in later years as his "biggest blunder", based on a letter George Gamow claimed to have received from him. The astrophysicist Mario Livio has cast doubt on this claim.
In late 2013, a team led by the Irish physicist Cormac O'Raifeartaigh discovered evidence that, shortly after learning of Hubble's observations of the recession of the galaxies, Einstein considered a steady-state model of the universe.
In a hitherto overlooked manuscript, apparently written in early 1931, Einstein explored a model of the expanding universe in which the density of matter remains constant due to a continuous creation of matter, a process that he associated with the cosmological constant.
As he stated in the paper, "In what follows, I would like to draw attention to a solution to equation (1) that can account for Hubbel's [sic] facts, and in which the density is constant over time" ... "If one considers a physically bounded volume, particles of matter will be continually leaving it. For the density to remain constant, new particles of matter must be continually formed in the volume from space."
It thus appears that Einstein considered a steady-state model of the expanding universe many years before Hoyle, Bondi and Gold. However, Einstein's steady-state model contained a fundamental flaw and he quickly abandoned the idea.
Energy momentum pseudotensor
Main article: Stress–energy–momentum pseudotensor
General relativity includes a dynamical spacetime, so it is difficult to see how to identify the conserved energy and momentum. Noether's theorem allows these quantities to be determined from a Lagrangian with translation invariance, but general covariance makes translation invariance into something of a gauge symmetry.
The energy and momentum derived within general relativity by Noether's prescriptions do not make a real tensor for this reason.
Einstein argued that this is true for a fundamental reason: the gravitational field could be made to vanish by a choice of coordinates. He maintained that the non-covariant energy momentum pseudotensor was, in fact, the best description of the energy momentum distribution in a gravitational field.
While the use of non-covariant objects like pseudotensors was criticized by Erwin Schrödinger and others, Einstein's approach has been echoed by physicists including Lev Landau and Evgeny Lifshitz.
Wormholes:
In 1935, Einstein collaborated with Nathan Rosen to produce a model of a wormhole, often called Einstein–Rosen bridges. His motivation was to model elementary particles with charge as a solution of gravitational field equations, in line with the program outlined in the paper "Do Gravitational Fields play an Important Role in the Constitution of the Elementary Particles?".
These solutions cut and pasted Schwarzschild black holes to make a bridge between two patches. Because these solutions included spacetime curvature without the presence of a physical body, Einstein and Rosen suggested that they could provide the beginnings of a theory that avoided the notion of point particles.
However, it was later found that Einstein–Rosen bridges are not stable.
Einstein–Cartan theory
Main article: Einstein–Cartan theory
In order to incorporate spinning point particles into general relativity, the affine connection needed to be generalized to include an antisymmetric part, called the torsion. This modification was made by Einstein and Cartan in the 1920s.
Equations of motion
Main article: Einstein–Infeld–Hoffmann equations
In general relativity, gravitational force is reimagined as curvature of spacetime. A curved path like an orbit is not the result of a force deflecting a body from an ideal straight-line path, but rather the body's attempt to fall freely through a background that is itself curved by the presence of other masses.
A remark by John Archibald Wheeler that has become proverbial among physicists summarizes the theory: "Spacetime tells matter how to move; matter tells spacetime how to curve." The Einstein field equations cover the latter aspect of the theory, relating the curvature of spacetime to the distribution of matter and energy.
The geodesic equation covers the former aspect, stating that freely falling bodies follow lines that are as straight as possible in a curved spacetime. Einstein regarded this as an "independent fundamental assumption" that had to be postulated in addition to the field equations in order to complete the theory.
Believing this to be a shortcoming in how general relativity was originally presented, he wished to derive it from the field equations themselves. Since the equations of general relativity are non-linear, a lump of energy made out of pure gravitational fields, like a black hole, would move on a trajectory which is determined by the Einstein field equations themselves, not by a new law.
Accordingly, Einstein proposed that the field equations would determine the path of a singular solution, like a black hole, to be a geodesic. Both physicists and philosophers have often repeated the assertion that the geodesic equation can be obtained from applying the field equations to the motion of a gravitational singularity, but this claim remains disputed.
Old quantum theory:
Main article: Old quantum theory
Photons and energy quanta
In a 1905 paper, Einstein postulated that light itself consists of localized particles (quanta). Einstein's light quanta were nearly universally rejected by all physicists, including Max Planck and Niels Bohr. This idea only became universally accepted in 1919, with Robert Millikan's detailed experiments on the photoelectric effect, and with the measurement of Compton scattering.
Einstein concluded that each wave of frequency f is associated with a collection of photons with energy hf each, where h is Planck's constant. He did not say much more, because he was not sure how the particles were related to the wave. But he did suggest that this idea would explain certain experimental results, notably the photoelectric effect.
Quantized atomic vibrations
Main article: Einstein solid
In 1907, Einstein proposed a model of matter where each atom in a lattice structure is an independent harmonic oscillator. In the Einstein model, each atom oscillates independently—a series of equally spaced quantized states for each oscillator.
Einstein was aware that getting the frequency of the actual oscillations would be difficult, but he nevertheless proposed this theory because it was a particularly clear demonstration that quantum mechanics could solve the specific heat problem in classical mechanics. Peter Debye refined this model.
Bose–Einstein statistics
Main article: Bose–Einstein statistics
In 1924, Einstein received a description of a statistical model from Indian physicist Satyendra Nath Bose, based on a counting method that assumed that light could be understood as a gas of indistinguishable particles. Einstein noted that Bose's statistics applied to some atoms as well as to the proposed light particles, and submitted his translation of Bose's paper to the Zeitschrift für Physik.
Einstein also published his own articles describing the model and its implications, among them the Bose–Einstein condensate phenomenon that some particulates should appear at very low temperatures.
It was not until 1995 that the first such condensate was produced experimentally by Eric Allin Cornell and Carl Wieman using ultra-cooling equipment built at the NIST–JILA laboratory at the University of Colorado at Boulder.
Bose–Einstein statistics are now used to describe the behaviors of any assembly of bosons. Einstein's sketches for this project may be seen in the Einstein Archive in the library of the Leiden University.
Wave–particle duality
Although the patent office promoted Einstein to Technical Examiner Second Class in 1906, he had not given up on academia.
In 1908, he became a Privatdozent at the University of Bern. In "Über die Entwicklung unserer Anschauungen über das Wesen und die Konstitution der Strahlung" ("The Development of our Views on the Composition and Essence of Radiation"), on the quantization of light, and in an earlier 1909 paper, Einstein showed that Max Planck's energy quanta must have well-defined momenta and act in some respects as independent, point-like particles.
This paper introduced the photon concept (although the name photon was introduced later by Gilbert N. Lewis in 1926) and inspired the notion of wave–particle duality in quantum mechanics. Einstein saw this wave–particle duality in radiation as concrete evidence for his conviction that physics needed a new, unified foundation.
Zero-point energy:
In a series of works completed from 1911 to 1913, Planck reformulated his 1900 quantum theory and introduced the idea of zero-point energy in his "second quantum theory". Soon, this idea attracted the attention of Einstein and his assistant Otto Stern.
Assuming the energy of rotating diatomic molecules contains zero-point energy, they then compared the theoretical specific heat of hydrogen gas with the experimental data. The numbers matched nicely.
However, after publishing the findings, they promptly withdrew their support, because they no longer had confidence in the correctness of the idea of zero-point energy.
Stimulated emission:
In 1917, at the height of his work on relativity, Einstein published an article in Physikalische Zeitschrift that proposed the possibility of stimulated emission, the physical process that makes possible the maser and the laser.
This article showed that the statistics of absorption and emission of light would only be consistent with Planck's distribution law if the emission of light into a mode with n photons would be enhanced statistically compared to the emission of light into an empty mode.
This paper was enormously influential in the later development of quantum mechanics, because it was the first paper to show that the statistics of atomic transitions had simple laws.
Matter waves:
Einstein discovered Louis de Broglie's work and supported his ideas, which were received skeptically at first. In another major paper from this era, Einstein observed that de Broglie waves could explain the quantization rules of Bohr and Sommerfeld. This paper would inspire Schrödinger's work of 1926.
Quantum mechanics:
Einstein's objections to quantum mechanics
Einstein played a major role in developing quantum theory, beginning with his 1905 paper on the photoelectric effect. However, he became displeased with modern quantum mechanics as it had evolved after 1925, despite its acceptance by other physicists. He was skeptical that the randomness of quantum mechanics was fundamental rather than the result of determinism, stating that God "is not playing at dice".
Until the end of his life, he continued to maintain that quantum mechanics was incomplete.
Bohr versus Einstein
Main article: Bohr–Einstein debates
The Bohr–Einstein debates were a series of public disputes about quantum mechanics between Einstein and Niels Bohr, who were two of its founders. Their debates are remembered because of their importance to the philosophy of science. Their debates would influence later interpretations of quantum mechanics.
Einstein–Podolsky–Rosen paradox
Main article: EPR paradox
Einstein never fully accepted quantum mechanics. While he recognized that it made correct predictions, he believed a more fundamental description of nature must be possible. Over the years he presented multiple arguments to this effect, but the one he preferred most dated to a debate with Bohr in 1930.
Einstein suggested a thought experiment in which two objects are allowed to interact and then moved apart a great distance from each other. The quantum-mechanical description of the two objects is a mathematical entity known as a wavefunction.
If the wavefunction that describes the two objects before their interaction is given, then the Schrödinger equation provides the wavefunction that describes them after their interaction. But because of what would later be called quantum entanglement, measuring one object would lead to an instantaneous change of the wavefunction describing the other object, no matter how far away it is.
Moreover, the choice of which measurement to perform upon the first object would affect what wavefunction could result for the second object. Einstein reasoned that no influence could propagate from the first object to the second instantaneously fast.
Indeed, he argued, physics depends on being able to tell one thing apart from another, and such instantaneous influences would call that into question. Because the true "physical condition" of the second object could not be immediately altered by an action done to the first, Einstein concluded, the wavefunction could not be that true physical condition, only an incomplete description of it.
A more famous version of this argument came in 1935, when Einstein published a paper with Boris Podolsky and Nathan Rosen that laid out what would become known as the EPR paradox.
In this thought experiment, two particles interact in such a way that the wavefunction describing them is entangled. Then, no matter how far the two particles were separated, a precise position measurement on one particle would imply the ability to predict, perfectly, the result of measuring the position of the other particle.
Likewise, a precise momentum measurement of one particle would result in an equally precise prediction for of the momentum of the other particle, without needing to disturb the other particle in any way.
They argued that no action taken on the first particle could instantaneously affect the other, since this would involve information being transmitted faster than light, which is forbidden by the theory of relativity. They invoked a principle, later known as the "EPR criterion of reality", positing that: "If, without in any way disturbing a system, we can predict with certainty (i.e., with probability equal to unity) the value of a physical quantity, then there exists an element of reality corresponding to that quantity."
From this, they inferred that the second particle must have a definite value of both position and of momentum prior to either quantity being measured. But quantum mechanics considers these two observables incompatible and thus does not associate simultaneous values for both to any system.
Einstein, Podolsky, and Rosen therefore concluded that quantum theory does not provide a complete description of reality.
In 1964, John Stewart Bell carried the analysis of quantum entanglement much further. He deduced that if measurements are performed independently on the two separated particles of an entangled pair, then the assumption that the outcomes depend upon hidden variables within each half implies a mathematical constraint on how the outcomes on the two measurements are correlated.
This constraint would later be called a Bell inequality. Bell then showed that quantum physics predicts correlations that violate this inequality. Consequently, the only way that hidden variables could explain the predictions of quantum physics is if they are "nonlocal", which is to say that somehow the two particles are able to interact instantaneously no matter how widely they ever become separated.
Bell argued that because an explanation of quantum phenomena in terms of hidden variables would require nonlocality, the EPR paradox "is resolved in the way which Einstein would have liked least".
Despite this, and although Einstein personally found the argument in the EPR paper overly complicated, that paper became among the most influential papers published in Physical Review. It is considered a centerpiece of the development of quantum information theory.
Unified field theory:
Main article: Classical unified field theories
Encouraged by his success with general relativity, Einstein sought an even more ambitious geometrical theory that would treat gravitation and electromagnetism as aspects of a single entity. In 1950, he described his unified field theory in a Scientific American article titled "On the Generalized Theory of Gravitation".
His attempt to find the most fundamental laws of nature won him praise but not success: a particularly conspicuous blemish of his model was that it did not accommodate the strong and weak nuclear forces, neither of which was well understood until many years after his death.
Although most researchers now believe that Einstein's approach to unifying physics was mistaken, his goal of a theory of everything is one to which his successors still aspire.
Other investigations:
Main article: Einstein's unsuccessful investigations
Einstein conducted other investigations that were unsuccessful and abandoned. These pertain to force, superconductivity, and other research.
Collaboration with other scientists
In addition to longtime collaborators Leopold Infeld, Nathan Rosen, Peter Bergmann and others, Einstein also had some one-shot collaborations with various scientists.
Einstein–de Haas experiment
Main article: Einstein–de Haas effect
In 1908, Owen Willans Richardson predicted that a change in the magnetic moment of a free body will cause this body to rotate. This effect is a consequence of the conservation of angular momentum and is strong enough to be observable in ferromagnetic materials.
Einstein and Wander Johannes de Haas published two papers in 1915 claiming the first experimental observation of the effect.
Measurements of this kind demonstrate that the phenomenon of magnetization is caused by the alignment (polarization) of the angular momenta of the electrons in the material along the axis of magnetization.
These measurements also allow the separation of the two contributions to the magnetization: that which is associated with the spin and with the orbital motion of the electrons.
Einstein as an inventor:
In 1926, Einstein and his former student Leó Szilárd co-invented (and in 1930, patented) the Einstein refrigerator. This absorption refrigerator was then revolutionary for having no moving parts and using only heat as an input.
On 11 November 1930, U.S. Patent 1,781,541 was awarded to Einstein and Leó Szilárd for the refrigerator. Their invention was not immediately put into commercial production, but the most promising of their patents were acquired by the Swedish company Electrolux.
Einstein also invented an electromagnetic pump, sound reproduction device, and several other household devices.
Non-scientific legacy
While traveling, Einstein wrote daily to his wife Elsa and adopted stepdaughters Margot and Ilse. The letters were included in the papers bequeathed to the Hebrew University of Jerusalem. Margot Einstein permitted the personal letters to be made available to the public, but requested that it not be done until twenty years after her death (she died in 1986).
Barbara Wolff, of the Hebrew University's Albert Einstein Archives, told the BBC that there are about 3,500 pages of private correspondence written between 1912 and 1955.
Einstein's right of publicity was litigated in 2015 in a federal district court in California. Although the court initially held that the right had expired, that ruling was immediately appealed, and the decision was later vacated in its entirety.
The underlying claims between the parties in that lawsuit were ultimately settled. The right is enforceable, and the Hebrew University of Jerusalem is the exclusive representative of that right. Corbis, successor to The Roger Richman Agency, licenses the use of his name and associated imagery, as agent for the university.
Mount Einstein in the Chugach Mountains of Alaska was named in 1955.
Mount Einstein in New Zealand's Paparoa Range was named after him in 1970 by the Department of Scientific and Industrial Research.
In popular culture:
Main article: Albert Einstein in popular culture
Einstein became one of the most famous scientific celebrities after the confirmation of his general theory of relativity in 1919. Although most of the public had little understanding of his work, he was widely recognized and admired.
In the period before World War II, The New Yorker published a vignette in their "The Talk of the Town" feature saying that Einstein was so well known in America that he would be stopped on the street by people wanting him to explain "that theory". Eventually he came to cope with unwanted enquirers by pretending to be someone else: "Pardon me, sorry! Always I am mistaken for Professor Einstein."
Einstein has been the subject of or inspiration for many novels, films, plays, and works of music. He is a favorite model for depictions of absent-minded professors; his expressive face and distinctive hairstyle have been widely copied and exaggerated.
Time magazine's Frederic Golden wrote that Einstein was "a cartoonist's dream come true".
Many popular quotations are often misattributed to him. For example, it is often claimed, erroneously, that he said, "The definition of insanity is doing the same thing over and over and expecting different results."
Awards and honors:
Main article: List of awards and honors received by Albert Einstein
Einstein received numerous awards and honors, and in 1922, he was awarded the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect". None of the nominations in 1921 met the criteria set by Alfred Nobel, so the 1921 prize was carried forward and awarded to Einstein in 1922.
Einsteinium, a synthetic chemical element, was named in his honor in 1955, a few months after his death.
Click on any of the following blue hyperlinks for more about Albertt Einstein:
Thermodynamic fluctuations and statistical physics
Main articles below:
Einstein's first paper submitted in 1900 to Annalen der Physik was on capillary attraction. It was published in 1901 with the title "Folgerungen aus den Capillaritätserscheinungen", which translates as "Conclusions from the capillarity phenomena".
Two papers he published in 1902–1903 (thermodynamics) attempted to interpret atomic phenomena from a statistical point of view. These papers were the foundation for the 1905 paper on Brownian motion, which showed that Brownian movement can be construed as firm evidence that molecules exist. His research in 1903 and 1904 was mainly concerned with the effect of finite atomic size on diffusion phenomena.
Theory of critical opalescence
Main article: Critical opalescence
Einstein returned to the problem of thermodynamic fluctuations, giving a treatment of the density variations in a fluid at its critical point. Ordinarily the density fluctuations are controlled by the second derivative of the free energy with respect to the density.
At the critical point, this derivative is zero, leading to large fluctuations. The effect of density fluctuations is that light of all wavelengths is scattered, making the fluid look milky white.
Einstein relates this to Rayleigh scattering, which is what happens when the fluctuation size is much smaller than the wavelength, and which explains why the sky is blue. Einstein quantitatively derived critical opalescence from a treatment of density fluctuations, and demonstrated how both the effect and Rayleigh scattering originate from the atomistic constitution of matter.
Special relativity:
Main article: History of special relativity
Einstein's "Zur Elektrodynamik bewegter Körper" ("On the Electrodynamics of Moving Bodies") was received on 30 June 1905 and published 26 September of that same year. It reconciled conflicts between Maxwell's equations (the laws of electricity and magnetism) and the laws of Newtonian mechanics by introducing changes to the laws of mechanics.
Observationally, the effects of these changes are most apparent at high speeds (where objects are moving at speeds close to the speed of light). The theory developed in this paper later became known as Einstein's special theory of relativity.
This paper predicted that, when measured in the frame of a relatively moving observer, a clock carried by a moving body would appear to slow down, and the body itself would contract in its direction of motion. This paper also argued that the idea of a luminiferous aether—one of the leading theoretical entities in physics at the time—was superfluous.
In his paper on mass–energy equivalence, Einstein produced E = mc2 as a consequence of his special relativity equations. Einstein's 1905 work on relativity remained controversial for many years, but was accepted by leading physicists, starting with Max Planck.
Einstein originally framed special relativity in terms of kinematics (the study of moving bodies). In 1908, Hermann Minkowski reinterpreted special relativity in geometric terms as a theory of spacetime. Einstein adopted Minkowski's formalism in his 1915 general theory of relativity.
General relativity:
General relativity and the equivalence principle
Main article: History of general relativity
See also:
General relativity (GR) is a theory of gravitation that was developed by Einstein between 1907 and 1915. According to it, the observed gravitational attraction between masses results from the warping of spacetime by those masses.
General relativity has developed into an essential tool in modern astrophysics; it provides the foundation for the current understanding of black holes, regions of space where gravitational attraction is so strong that not even light can escape.
As Einstein later said, the reason for the development of general relativity was that the preference of inertial motions within special relativity was unsatisfactory, while a theory which from the outset prefers no state of motion (even accelerated ones) should appear more satisfactory.
Consequently, in 1907 he published an article on acceleration under special relativity. In that article titled "On the Relativity Principle and the Conclusions Drawn from It", he argued that free fall is really inertial motion, and that for a free-falling observer the rules of special relativity must apply. This argument is called the equivalence principle.
In the same article, Einstein also predicted the phenomena of:
In 1911, Einstein published another article "On the Influence of Gravitation on the Propagation of Light" expanding on the 1907 article, in which he estimated the amount of deflection of light by massive bodies. Thus, the theoretical prediction of general relativity could for the first time be tested experimentally.
Gravitational waves:
In 1916, Einstein predicted gravitational waves, ripples in the curvature of spacetime which propagate as waves, traveling outward from the source, transporting energy as gravitational radiation.
The existence of gravitational waves is possible under general relativity due to its Lorentz invariance which brings the concept of a finite speed of propagation of the physical interactions of gravity with it.
By contrast, gravitational waves cannot exist in the Newtonian theory of gravitation, which postulates that the physical interactions of gravity propagate at infinite speed.
The first, indirect, detection of gravitational waves came in the 1970s through observation of a pair of closely orbiting neutron stars, PSR B1913+16. The explanation for the decay in their orbital period was that they were emitting gravitational waves.
Einstein's prediction was confirmed on 11 February 2016, when researchers at LIGO published the first observation of gravitational waves, detected on Earth on 14 September 2015, nearly one hundred years after the prediction.
Hole argument and Entwurf theory:
While developing general relativity, Einstein became confused about the gauge invariance in the theory. He formulated an argument that led him to conclude that a general relativistic field theory is impossible. He gave up looking for fully generally covariant tensor equations and searched for equations that would be invariant under general linear transformations only.
In June 1913, the Entwurf ('draft') theory was the result of these investigations. As its name suggests, it was a sketch of a theory, less elegant and more difficult than general relativity, with the equations of motion supplemented by additional gauge fixing conditions. After more than two years of intensive work, Einstein realized that the hole argument was mistaken and abandoned the theory in November 1915.
Physical cosmology
Main article: Physical cosmology
In 1917, Einstein applied the general theory of relativity to the structure of the universe as a whole. He discovered that the general field equations predicted a universe that was dynamic, either contracting or expanding. As observational evidence for a dynamic universe was lacking at the time, Einstein introduced a new term, the cosmological constant, into the field equations, in order to allow the theory to predict a static universe.
The modified field equations predicted a static universe of closed curvature, in accordance with Einstein's understanding of Mach's principle in these years. This model became known as the Einstein World or Einstein's static universe.
Following the discovery of the recession of the galaxies by Edwin Hubble in 1929, Einstein abandoned his static model of the universe, and proposed two dynamic models of the cosmos, the Friedmann–Einstein universe of 1931 and the Einstein–de Sitter universe of 1932.
In each of these models, Einstein discarded the cosmological constant, claiming that it was "in any case theoretically unsatisfactory".
In many Einstein biographies, it is claimed that Einstein referred to the cosmological constant in later years as his "biggest blunder", based on a letter George Gamow claimed to have received from him. The astrophysicist Mario Livio has cast doubt on this claim.
In late 2013, a team led by the Irish physicist Cormac O'Raifeartaigh discovered evidence that, shortly after learning of Hubble's observations of the recession of the galaxies, Einstein considered a steady-state model of the universe.
In a hitherto overlooked manuscript, apparently written in early 1931, Einstein explored a model of the expanding universe in which the density of matter remains constant due to a continuous creation of matter, a process that he associated with the cosmological constant.
As he stated in the paper, "In what follows, I would like to draw attention to a solution to equation (1) that can account for Hubbel's [sic] facts, and in which the density is constant over time" ... "If one considers a physically bounded volume, particles of matter will be continually leaving it. For the density to remain constant, new particles of matter must be continually formed in the volume from space."
It thus appears that Einstein considered a steady-state model of the expanding universe many years before Hoyle, Bondi and Gold. However, Einstein's steady-state model contained a fundamental flaw and he quickly abandoned the idea.
Energy momentum pseudotensor
Main article: Stress–energy–momentum pseudotensor
General relativity includes a dynamical spacetime, so it is difficult to see how to identify the conserved energy and momentum. Noether's theorem allows these quantities to be determined from a Lagrangian with translation invariance, but general covariance makes translation invariance into something of a gauge symmetry.
The energy and momentum derived within general relativity by Noether's prescriptions do not make a real tensor for this reason.
Einstein argued that this is true for a fundamental reason: the gravitational field could be made to vanish by a choice of coordinates. He maintained that the non-covariant energy momentum pseudotensor was, in fact, the best description of the energy momentum distribution in a gravitational field.
While the use of non-covariant objects like pseudotensors was criticized by Erwin Schrödinger and others, Einstein's approach has been echoed by physicists including Lev Landau and Evgeny Lifshitz.
Wormholes:
In 1935, Einstein collaborated with Nathan Rosen to produce a model of a wormhole, often called Einstein–Rosen bridges. His motivation was to model elementary particles with charge as a solution of gravitational field equations, in line with the program outlined in the paper "Do Gravitational Fields play an Important Role in the Constitution of the Elementary Particles?".
These solutions cut and pasted Schwarzschild black holes to make a bridge between two patches. Because these solutions included spacetime curvature without the presence of a physical body, Einstein and Rosen suggested that they could provide the beginnings of a theory that avoided the notion of point particles.
However, it was later found that Einstein–Rosen bridges are not stable.
Einstein–Cartan theory
Main article: Einstein–Cartan theory
In order to incorporate spinning point particles into general relativity, the affine connection needed to be generalized to include an antisymmetric part, called the torsion. This modification was made by Einstein and Cartan in the 1920s.
Equations of motion
Main article: Einstein–Infeld–Hoffmann equations
In general relativity, gravitational force is reimagined as curvature of spacetime. A curved path like an orbit is not the result of a force deflecting a body from an ideal straight-line path, but rather the body's attempt to fall freely through a background that is itself curved by the presence of other masses.
A remark by John Archibald Wheeler that has become proverbial among physicists summarizes the theory: "Spacetime tells matter how to move; matter tells spacetime how to curve." The Einstein field equations cover the latter aspect of the theory, relating the curvature of spacetime to the distribution of matter and energy.
The geodesic equation covers the former aspect, stating that freely falling bodies follow lines that are as straight as possible in a curved spacetime. Einstein regarded this as an "independent fundamental assumption" that had to be postulated in addition to the field equations in order to complete the theory.
Believing this to be a shortcoming in how general relativity was originally presented, he wished to derive it from the field equations themselves. Since the equations of general relativity are non-linear, a lump of energy made out of pure gravitational fields, like a black hole, would move on a trajectory which is determined by the Einstein field equations themselves, not by a new law.
Accordingly, Einstein proposed that the field equations would determine the path of a singular solution, like a black hole, to be a geodesic. Both physicists and philosophers have often repeated the assertion that the geodesic equation can be obtained from applying the field equations to the motion of a gravitational singularity, but this claim remains disputed.
Old quantum theory:
Main article: Old quantum theory
Photons and energy quanta
In a 1905 paper, Einstein postulated that light itself consists of localized particles (quanta). Einstein's light quanta were nearly universally rejected by all physicists, including Max Planck and Niels Bohr. This idea only became universally accepted in 1919, with Robert Millikan's detailed experiments on the photoelectric effect, and with the measurement of Compton scattering.
Einstein concluded that each wave of frequency f is associated with a collection of photons with energy hf each, where h is Planck's constant. He did not say much more, because he was not sure how the particles were related to the wave. But he did suggest that this idea would explain certain experimental results, notably the photoelectric effect.
Quantized atomic vibrations
Main article: Einstein solid
In 1907, Einstein proposed a model of matter where each atom in a lattice structure is an independent harmonic oscillator. In the Einstein model, each atom oscillates independently—a series of equally spaced quantized states for each oscillator.
Einstein was aware that getting the frequency of the actual oscillations would be difficult, but he nevertheless proposed this theory because it was a particularly clear demonstration that quantum mechanics could solve the specific heat problem in classical mechanics. Peter Debye refined this model.
Bose–Einstein statistics
Main article: Bose–Einstein statistics
In 1924, Einstein received a description of a statistical model from Indian physicist Satyendra Nath Bose, based on a counting method that assumed that light could be understood as a gas of indistinguishable particles. Einstein noted that Bose's statistics applied to some atoms as well as to the proposed light particles, and submitted his translation of Bose's paper to the Zeitschrift für Physik.
Einstein also published his own articles describing the model and its implications, among them the Bose–Einstein condensate phenomenon that some particulates should appear at very low temperatures.
It was not until 1995 that the first such condensate was produced experimentally by Eric Allin Cornell and Carl Wieman using ultra-cooling equipment built at the NIST–JILA laboratory at the University of Colorado at Boulder.
Bose–Einstein statistics are now used to describe the behaviors of any assembly of bosons. Einstein's sketches for this project may be seen in the Einstein Archive in the library of the Leiden University.
Wave–particle duality
Although the patent office promoted Einstein to Technical Examiner Second Class in 1906, he had not given up on academia.
In 1908, he became a Privatdozent at the University of Bern. In "Über die Entwicklung unserer Anschauungen über das Wesen und die Konstitution der Strahlung" ("The Development of our Views on the Composition and Essence of Radiation"), on the quantization of light, and in an earlier 1909 paper, Einstein showed that Max Planck's energy quanta must have well-defined momenta and act in some respects as independent, point-like particles.
This paper introduced the photon concept (although the name photon was introduced later by Gilbert N. Lewis in 1926) and inspired the notion of wave–particle duality in quantum mechanics. Einstein saw this wave–particle duality in radiation as concrete evidence for his conviction that physics needed a new, unified foundation.
Zero-point energy:
In a series of works completed from 1911 to 1913, Planck reformulated his 1900 quantum theory and introduced the idea of zero-point energy in his "second quantum theory". Soon, this idea attracted the attention of Einstein and his assistant Otto Stern.
Assuming the energy of rotating diatomic molecules contains zero-point energy, they then compared the theoretical specific heat of hydrogen gas with the experimental data. The numbers matched nicely.
However, after publishing the findings, they promptly withdrew their support, because they no longer had confidence in the correctness of the idea of zero-point energy.
Stimulated emission:
In 1917, at the height of his work on relativity, Einstein published an article in Physikalische Zeitschrift that proposed the possibility of stimulated emission, the physical process that makes possible the maser and the laser.
This article showed that the statistics of absorption and emission of light would only be consistent with Planck's distribution law if the emission of light into a mode with n photons would be enhanced statistically compared to the emission of light into an empty mode.
This paper was enormously influential in the later development of quantum mechanics, because it was the first paper to show that the statistics of atomic transitions had simple laws.
Matter waves:
Einstein discovered Louis de Broglie's work and supported his ideas, which were received skeptically at first. In another major paper from this era, Einstein observed that de Broglie waves could explain the quantization rules of Bohr and Sommerfeld. This paper would inspire Schrödinger's work of 1926.
Quantum mechanics:
Einstein's objections to quantum mechanics
Einstein played a major role in developing quantum theory, beginning with his 1905 paper on the photoelectric effect. However, he became displeased with modern quantum mechanics as it had evolved after 1925, despite its acceptance by other physicists. He was skeptical that the randomness of quantum mechanics was fundamental rather than the result of determinism, stating that God "is not playing at dice".
Until the end of his life, he continued to maintain that quantum mechanics was incomplete.
Bohr versus Einstein
Main article: Bohr–Einstein debates
The Bohr–Einstein debates were a series of public disputes about quantum mechanics between Einstein and Niels Bohr, who were two of its founders. Their debates are remembered because of their importance to the philosophy of science. Their debates would influence later interpretations of quantum mechanics.
Einstein–Podolsky–Rosen paradox
Main article: EPR paradox
Einstein never fully accepted quantum mechanics. While he recognized that it made correct predictions, he believed a more fundamental description of nature must be possible. Over the years he presented multiple arguments to this effect, but the one he preferred most dated to a debate with Bohr in 1930.
Einstein suggested a thought experiment in which two objects are allowed to interact and then moved apart a great distance from each other. The quantum-mechanical description of the two objects is a mathematical entity known as a wavefunction.
If the wavefunction that describes the two objects before their interaction is given, then the Schrödinger equation provides the wavefunction that describes them after their interaction. But because of what would later be called quantum entanglement, measuring one object would lead to an instantaneous change of the wavefunction describing the other object, no matter how far away it is.
Moreover, the choice of which measurement to perform upon the first object would affect what wavefunction could result for the second object. Einstein reasoned that no influence could propagate from the first object to the second instantaneously fast.
Indeed, he argued, physics depends on being able to tell one thing apart from another, and such instantaneous influences would call that into question. Because the true "physical condition" of the second object could not be immediately altered by an action done to the first, Einstein concluded, the wavefunction could not be that true physical condition, only an incomplete description of it.
A more famous version of this argument came in 1935, when Einstein published a paper with Boris Podolsky and Nathan Rosen that laid out what would become known as the EPR paradox.
In this thought experiment, two particles interact in such a way that the wavefunction describing them is entangled. Then, no matter how far the two particles were separated, a precise position measurement on one particle would imply the ability to predict, perfectly, the result of measuring the position of the other particle.
Likewise, a precise momentum measurement of one particle would result in an equally precise prediction for of the momentum of the other particle, without needing to disturb the other particle in any way.
They argued that no action taken on the first particle could instantaneously affect the other, since this would involve information being transmitted faster than light, which is forbidden by the theory of relativity. They invoked a principle, later known as the "EPR criterion of reality", positing that: "If, without in any way disturbing a system, we can predict with certainty (i.e., with probability equal to unity) the value of a physical quantity, then there exists an element of reality corresponding to that quantity."
From this, they inferred that the second particle must have a definite value of both position and of momentum prior to either quantity being measured. But quantum mechanics considers these two observables incompatible and thus does not associate simultaneous values for both to any system.
Einstein, Podolsky, and Rosen therefore concluded that quantum theory does not provide a complete description of reality.
In 1964, John Stewart Bell carried the analysis of quantum entanglement much further. He deduced that if measurements are performed independently on the two separated particles of an entangled pair, then the assumption that the outcomes depend upon hidden variables within each half implies a mathematical constraint on how the outcomes on the two measurements are correlated.
This constraint would later be called a Bell inequality. Bell then showed that quantum physics predicts correlations that violate this inequality. Consequently, the only way that hidden variables could explain the predictions of quantum physics is if they are "nonlocal", which is to say that somehow the two particles are able to interact instantaneously no matter how widely they ever become separated.
Bell argued that because an explanation of quantum phenomena in terms of hidden variables would require nonlocality, the EPR paradox "is resolved in the way which Einstein would have liked least".
Despite this, and although Einstein personally found the argument in the EPR paper overly complicated, that paper became among the most influential papers published in Physical Review. It is considered a centerpiece of the development of quantum information theory.
Unified field theory:
Main article: Classical unified field theories
Encouraged by his success with general relativity, Einstein sought an even more ambitious geometrical theory that would treat gravitation and electromagnetism as aspects of a single entity. In 1950, he described his unified field theory in a Scientific American article titled "On the Generalized Theory of Gravitation".
His attempt to find the most fundamental laws of nature won him praise but not success: a particularly conspicuous blemish of his model was that it did not accommodate the strong and weak nuclear forces, neither of which was well understood until many years after his death.
Although most researchers now believe that Einstein's approach to unifying physics was mistaken, his goal of a theory of everything is one to which his successors still aspire.
Other investigations:
Main article: Einstein's unsuccessful investigations
Einstein conducted other investigations that were unsuccessful and abandoned. These pertain to force, superconductivity, and other research.
Collaboration with other scientists
In addition to longtime collaborators Leopold Infeld, Nathan Rosen, Peter Bergmann and others, Einstein also had some one-shot collaborations with various scientists.
Einstein–de Haas experiment
Main article: Einstein–de Haas effect
In 1908, Owen Willans Richardson predicted that a change in the magnetic moment of a free body will cause this body to rotate. This effect is a consequence of the conservation of angular momentum and is strong enough to be observable in ferromagnetic materials.
Einstein and Wander Johannes de Haas published two papers in 1915 claiming the first experimental observation of the effect.
Measurements of this kind demonstrate that the phenomenon of magnetization is caused by the alignment (polarization) of the angular momenta of the electrons in the material along the axis of magnetization.
These measurements also allow the separation of the two contributions to the magnetization: that which is associated with the spin and with the orbital motion of the electrons.
Einstein as an inventor:
In 1926, Einstein and his former student Leó Szilárd co-invented (and in 1930, patented) the Einstein refrigerator. This absorption refrigerator was then revolutionary for having no moving parts and using only heat as an input.
On 11 November 1930, U.S. Patent 1,781,541 was awarded to Einstein and Leó Szilárd for the refrigerator. Their invention was not immediately put into commercial production, but the most promising of their patents were acquired by the Swedish company Electrolux.
Einstein also invented an electromagnetic pump, sound reproduction device, and several other household devices.
Non-scientific legacy
While traveling, Einstein wrote daily to his wife Elsa and adopted stepdaughters Margot and Ilse. The letters were included in the papers bequeathed to the Hebrew University of Jerusalem. Margot Einstein permitted the personal letters to be made available to the public, but requested that it not be done until twenty years after her death (she died in 1986).
Barbara Wolff, of the Hebrew University's Albert Einstein Archives, told the BBC that there are about 3,500 pages of private correspondence written between 1912 and 1955.
Einstein's right of publicity was litigated in 2015 in a federal district court in California. Although the court initially held that the right had expired, that ruling was immediately appealed, and the decision was later vacated in its entirety.
The underlying claims between the parties in that lawsuit were ultimately settled. The right is enforceable, and the Hebrew University of Jerusalem is the exclusive representative of that right. Corbis, successor to The Roger Richman Agency, licenses the use of his name and associated imagery, as agent for the university.
Mount Einstein in the Chugach Mountains of Alaska was named in 1955.
Mount Einstein in New Zealand's Paparoa Range was named after him in 1970 by the Department of Scientific and Industrial Research.
In popular culture:
Main article: Albert Einstein in popular culture
Einstein became one of the most famous scientific celebrities after the confirmation of his general theory of relativity in 1919. Although most of the public had little understanding of his work, he was widely recognized and admired.
In the period before World War II, The New Yorker published a vignette in their "The Talk of the Town" feature saying that Einstein was so well known in America that he would be stopped on the street by people wanting him to explain "that theory". Eventually he came to cope with unwanted enquirers by pretending to be someone else: "Pardon me, sorry! Always I am mistaken for Professor Einstein."
Einstein has been the subject of or inspiration for many novels, films, plays, and works of music. He is a favorite model for depictions of absent-minded professors; his expressive face and distinctive hairstyle have been widely copied and exaggerated.
Time magazine's Frederic Golden wrote that Einstein was "a cartoonist's dream come true".
Many popular quotations are often misattributed to him. For example, it is often claimed, erroneously, that he said, "The definition of insanity is doing the same thing over and over and expecting different results."
Awards and honors:
Main article: List of awards and honors received by Albert Einstein
Einstein received numerous awards and honors, and in 1922, he was awarded the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect". None of the nominations in 1921 met the criteria set by Alfred Nobel, so the 1921 prize was carried forward and awarded to Einstein in 1922.
Einsteinium, a synthetic chemical element, was named in his honor in 1955, a few months after his death.
Click on any of the following blue hyperlinks for more about Albertt Einstein:
- See also:
- Publications
- Bern Historical Museum (Einstein Museum)
- Einstein notation
- Frist Campus Center at Princeton University – room 302 is associated with Einstein. The center was once the Palmer Physical Laboratory.
- Heinrich Burkhardt
- Heinrich Zangger
- History of gravitational theory
- List of coupled cousins
- List of German inventors and discoverers
- List of Jewish Nobel laureates
- List of peace activists
- Relativity priority dispute
- Sticky bead argument
- Albert Einstein at Curlie
- Works by Albert Einstein at Project Gutenberg
- Works by or about Albert Einstein at Internet Archive
- Works by Albert Einstein at LibriVox (public domain audiobooks)
- Einstein's Personal Correspondence: Religion, Politics, The Holocaust, and Philosophy Shapell Manuscript Foundation
- Federal Bureau of Investigation file on Albert Einstein
- Einstein and his love of music, Physics World
- Albert Einstein on Nobelprize.org including the Nobel Lecture 11 July 1923 Fundamental ideas and problems of the theory of relativity
- Albert Einstein Collection at Brandeis University
- The Collected Papers of Albert Einstein "Digital Einstein" at Princeton University
- Newspaper clippings about Albert Einstein in the 20th Century Press Archives of the ZBW
- Home page of Albert Einstein at The Institute for Advanced Study
- Albert – The Digital Repository of the IAS, which contains many digitized original documents and photographs