Photographed by Oren J. Turner (1947)
March 14 1879
|Died||April 18 1955 (aged 76)|
|Residence|| Germany, Italy, |
|Nationality|| Germany, Switzerland, |
|Institutions||Swiss Patent Office (Berne)|
Univ. of Zürich
Prussian Acad. of Sciences
Kaiser Wilhelm Inst.
Univ. of Leiden
Inst. for Advanced Study
|Alma mater||ETH Zürich|
|Academic advisor||Alfred Kleiner|
|Known for||General relativity|
Einstein field equations
Unified Field Theory
|Notable prizes|| Nobel Prize in Physics (1921)|
Copley Medal (1925)
Max Planck medal (1929)
Albert Einstein (March 14, 1879 – April 18, 1955) was a German-born theoretical physicist. He is best known for his theory of relativity and specifically the equation , which indicates the relationship between mass and energy (or mass-energy equivalence). Einstein 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."
Einstein's many contributions to physics include his special theory of relativity, which reconciled mechanics with electromagnetism, and his general theory of relativity which extended the principle of relativity to non-uniform motion, creating a new theory of gravitation. His other contributions include relativistic cosmology, capillary action, critical opalescence, classical problems of statistical mechanics and their application to quantum theory, an explanation of the Brownian movement of molecules, atomic transition probabilities, the quantum theory of a monatomic gas, thermal properties of light with low radiation density (which laid the foundation for the photon theory), a theory of radiation including stimulated emission, the conception of a unified field theory, and the geometrization of physics.
- 1 Youth and schooling
- 2 The Patent Office
- 3 The Annus Mirabilis
- 4 Light and General Relativity
- 5 The Nobel Prize
- 6 Unified Field Theory
- 7 Collaboration and conflict
- 8 Religious views
- 9 Politics
- 10 Death
- 11 Legacy
- 12 Honors
- 13 Major works
- 14 Notes
- 15 References
- 16 External links
- 17 Credits
Works by Albert Einstein include more than 50 scientific papers and also non-scientific books. In 1999 Einstein was named TIME magazine's "Person of the Century," and a poll of prominent physicists named him the greatest physicist of all time. In popular culture, the name "Einstein" has become synonymous with genius.
Youth and schooling
Albert Einstein was born into a Jewish family in Ulm, Württemberg, Germany. His father was Hermann Einstein, a salesman and engineer. His mother was Pauline Einstein (née Koch). Although Albert had early speech difficulties, he was a top student in elementary school.
In 1880, the family moved to Munich, where his father and his uncle founded a company, Elektrotechnische Fabrik J. Einstein & Cie that manufactured electrical equipment, providing the first lighting for the Oktoberfest and cabling for the Munich suburb of Schwabing. The Einsteins were not observant of Jewish religious practices, and Albert attended a Catholic elementary school. At his mother's insistence, he took violin lessons, and although he disliked them and eventually quit, he would later take great pleasure in Mozart's violin sonatas.
When Albert was five, his father showed him a pocket compass. Albert realized that something in empty space was moving the needle and later stated that this experience made "a deep and lasting impression". As he grew, Albert built models and mechanical devices for fun, and began to show a talent for mathematics.
In 1889, family friend Max Talmud (later: Talmey), a medical student, introduced the ten-year-old Albert to key science and philosophy texts, including Kant's Critique of Pure Reason and Euclid's Elements (Einstein called it the "holy little geometry book"). From Euclid, Albert began to understand deductive reasoning (integral to theoretical physics), and by the age of 12, he learned Euclidean geometry from a school booklet. Soon thereafter he began to investigate calculus.
In his early teens, Albert attended the new and progressive Luitpold Gymnasium. His father intended for him to pursue electrical engineering, but Albert clashed with authorities and resented the school regimen. He later wrote that the spirit of learning and creative thought were lost in strict rote learning.
In 1894, when Einstein was 15, his father's business failed, and the Einstein family moved to Italy, first to Milan and then, after a few months, to Pavia. During this time, Albert wrote his first scientific work, "The Investigation of the State of Aether in Magnetic Fields." Albert had been left behind in Munich to finish high school, but in the spring of 1895, he withdrew to join his family in Pavia, convincing the school to let him go by using a doctor's note.
Rather than completing high school, Albert decided to apply directly to the ETH Zürich, the Swiss Federal Institute of Technology in Zurich, Switzerland. Without a school certificate, he was required to take an entrance examination. He did not pass. Einstein wrote that it was in that same year, at age 16, that he first performed his famous thought experiment, visualizing traveling alongside a beam of light.
The Einsteins sent Albert to Aarau, Switzerland to finish secondary school. While lodging with the family of Professor Jost Winteler, he fell in love with the family's daughter, Sofia Marie-Jeanne Amanda Winteler, called "Marie." (Albert's sister, Maja, his confidant, later married Paul Winteler.) In Aarau, Albert studied Maxwell's electromagnetic theory. In 1896, he graduated at age 17, renounced his German citizenship to avoid military service (with his father's approval), and finally enrolled in the mathematics program at ETH. On February 21, 1901, he gained Swiss citizenship, which he never revoked. Marie moved to Olsberg, Switzerland for a teaching post.
In 1896, Einstein's future wife, Mileva Marić, also enrolled at ETH, as the only woman studying mathematics. During the next few years, Einstein and Marić's friendship developed into romance. Einstein's mother objected because she thought Marić "too old," not Jewish, and "physically defective." This conclusion is from Einstein's correspondence with Marić. Lieserl is first mentioned in a letter from Einstein to Marić (who was abroad at the time of Lieserl's birth) dated February 4, 1902, from Novi Sad, Hungary. Her fate is unknown.
Einstein graduated in 1900 from ETH with a degree in physics. That same year, Einstein's friend Michele Besso introduced him to the work of Ernst Mach. The next year, Einstein published a paper in the prestigious Annalen der Physik on the capillary forces of a straw.
The Patent Office
Following graduation, Einstein could not find a teaching post. After almost two years of searching, a former classmate's father helped him get a job in Bern, at the Federal Office for Intellectual Property, the patent office, as an assistant examiner. His responsibility was evaluating patent applications for electromagnetic devices. In 1903, Einstein's position at the Swiss Patent Office was made permanent, although he was passed over for promotion until he "fully mastered machine technology".
Einstein's college friend, Michele Besso, also worked at the patent office. With friends they met in Bern, they formed a weekly discussion club on science and philosophy, jokingly named "The Olympia Academy." Their readings included Poincaré, Mach and Hume, who influenced Einstein's scientific and philosophical outlook.
While this period at the patent office has often been cited as a waste of Einstein's talents, or as a temporary job with no connection to his interests in physics, the historian of science Peter Galison has argued that Einstein's work there was connected to his later interests. Much of that work related to questions about transmission of electric signals and electrical-mechanical synchronization of time: two technical problems of the day that show up conspicuously in the thought experiments that led Einstein to his radical conclusions about the nature of light and the fundamental connection between space and time.
Einstein married Mileva Marić on January 6, 1903, and their relationship was, for a time, a personal and intellectual partnership. In a letter to her, Einstein wrote of Mileva as "a creature who is my equal and who is as strong and independent as I am." There has been debate about whether Marić influenced Einstein's work; most historians do not think she made major contributions, however. On May 14, 1904, Albert and Mileva's first son, Hans Albert Einstein, was born. Their second son, Eduard Einstein, was born on July 28, 1910.
The Annus Mirabilis
In 1905, while working in the patent office, Einstein published four times in the Annalen der Physik, the leading German physics journal. These are the papers that history has come to call the Annus Mirabilis Papers:
- His paper on the particulate nature of light put forward the idea that certain experimental results, notably the photoelectric effect, could be simply understood from the postulate that light interacts with matter as discrete "packets" (quanta) of energy, an idea that had been introduced by Max Planck in 1900 as a purely mathematical manipulation, and which seemed to contradict contemporary wave theories of light. This was the only work of Einstein's that he himself pronounced as "revolutionary."
- His paper on Brownian motion explained the random movement of very small objects as direct evidence of molecular action, thus supporting the atomic theory.
- His paper on the electrodynamics of moving bodies proposed the radical theory of special relativity, which showed that the independence of an observer's state of motion on the observed speed of light requires fundamental changes to the notion of simultaneity. The consequences of this include the time-space frame of a moving body slowing down and contracting (in the direction of motion) relative to the frame of the observer. 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 the equivalence of matter and energy (previously considered to be distinct concepts), Einstein deduced from his equations of special relativity what would later become the most famous expression in all of science: , suggesting that tiny amounts of mass could be converted into huge amounts of energy.
All four papers are today recognized as tremendous achievements—and hence 1905 is known as Einstein's "Wonderful Year." At the time, however, they were not noticed by most physicists as being important, and many of those who did notice them rejected them outright. Some of this work—such as the theory of light quanta—would remain controversial for years.
At the age of 26, having studied under Alfred Kleiner, Professor of Experimental Physics, Einstein was awarded a PhD by the University of Zurich. His dissertation was entitled "A new determination of molecular dimensions."
Light and General Relativity
In 1906, the patent office promoted Einstein to Technical Examiner Second Class, but he was not giving up on academia. In 1908, he became a privatdozent at the University of Bern. In 1910, he wrote a paper on critical opalescence that described the cumulative effect of light scattered by individual molecules in the atmosphere, i.e., why the sky is blue.
During 1909, Einstein published "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. In this 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 term itself was introduced by Gilbert N. Lewis in 1926) and inspired the notion of wave–particle duality in quantum mechanics.
In 1911, Einstein became an associate professor at the University of Zurich. However, shortly afterward, he accepted a full professorship at the Charles University of Prague. While in Prague, Einstein published a paper about the effects of gravity on light, specifically the gravitational redshift and the gravitational deflection of light. The paper appealed to astronomers to find ways of detecting the deflection during a solar eclipse. German astronomer Erwin Freundlich publicized Einstein's challenge to scientists around the world.
In 1912, Einstein returned to Switzerland to accept a professorship at his alma mater, the ETH. There he met mathematician Marcel Grossmann who introduced him to Riemannian geometry, and at the recommendation of Italian mathematician Tullio Levi-Civita, Einstein began exploring the usefulness of general covariance (essentially the use of tensors) for his gravitational theory. Although for a while Einstein thought that there were problems with that approach, he later returned to it and by late 1915 had published his general theory of relativity in the form that is still used today. This theory explains gravitation as distortion of the structure of spacetime by matter, affecting the inertial motion of other matter.
After many relocations, Mileva established a permanent home with the children in Zurich in 1914, just before the start of World War I. Einstein continued on alone to Germany, more precisely to Berlin, where he became a member of the Preußische Akademie der Wissenschaften. As part of the arrangements for his new position, he also became a professor at the University of Berlin, although with a special clause freeing him from most teaching obligations. From 1914 to 1932 he was also director of the Kaiser Wilhelm Institute for physics.
During World War I, the speeches and writings of Central Powers scientists were only available to Central Powers academics for national security reasons. Some of Einstein's work did reach the United Kingdom and the USA through the efforts of the Austrian Paul Ehrenfest and physicists in the Netherlands, especially 1902 Nobel Prize-winner Hendrik Lorentz and Willem de Sitter of the Leiden University. After the war ended, Einstein maintained his relationship with the Leiden University, accepting a contract as a buitengewoon hoogleraar; he travelled to Holland regularly to lecture there between 1920 and 1930.
In 1917, Einstein published an article in Physikalische Zeitschrift that proposed the possibility of stimulated emission, the physical technique that makes possible the laser}. He also published a paper introducing a new notion, a cosmological constant, into the general theory of relativity in an attempt to model the behavior of the entire universe.
1917 was the year astronomers began taking Einstein up on his 1911 challenge from Prague. The Mount Wilson Observatory in California, USA, published a solar spectroscopic analysis that showed no gravitational redshift. In 1918, the Lick Observatory, also in California, announced that they too had disproven Einstein's prediction, although their findings were not published.
However, in May 1919, a team led by British astronomer Arthur Eddington claimed to have confirmed Einstein's prediction of gravitational deflection of starlight by the Sun while photographing a solar eclipse in Sobral northern Brazil and Principe. On November 7, 1919, leading British newspaper The Times printed a banner headline that read: "Revolution in Science – New Theory of the Universe – Newtonian Ideas Overthrown". In an interview Nobel laureate Max Born praised general relativity as the "greatest feat of human thinking about nature"; fellow laureate Paul Dirac was quoted saying it was "probably the greatest scientific discovery ever made".
In their excitement, the world media made Albert Einstein world-famous. Ironically, later examination of the photographs taken on the Eddington expedition showed that the experimental uncertainty was of about the same magnitude as the effect Eddington claimed to have demonstrated, and in 1962 a British expedition concluded that the method used was inherently unreliable. The deflection of light during an eclipse has, however, been more accurately measured (and confirmed) by later observations.
There was some resentment toward the newcomer Einstein's fame in the scientific community, notably among German physicists, who would later start the Deutsche Physik (German Physics) movement.
Having lived apart for five years, Einstein and Mileva divorced on February 14, 1919. On June 2 of that year, Einstein married Elsa Löwenthal, who had nursed him through an illness. Elsa was Albert's first cousin (maternally) and his second cousin (paternally). Together the Einsteins raised Margot and Ilse, Elsa's daughters from her first marriage.
The Nobel Prize
In 1921 Einstein was awarded the Nobel Prize in Physics, "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect." This refers to his 1905 paper on the photoelectric effect: "On a Heuristic Viewpoint Concerning the Production and Transformation of Light," which was well supported by the experimental evidence by that time. The presentation speech began by mentioning "his theory of relativity [which had] been the subject of lively debate in philosophical circles [and] also has astrophysical implications which are being rigorously examined at the present time." As per their divorce settlement, Einstein gave the Nobel prize money to his first wife, Mileva Marić, who was struggling financially to support their two sons and her parents.
Einstein travelled to New York City in the United States for the first time on April 2, 1921. When asked where he got his scientific ideas, Einstein explained that he believed scientific work best proceeds from an examination of physical reality and a search for underlying axioms, with consistent explanations that apply in all instances and avoid contradicting each other. He also recommended theories with visualizable results.
Unified Field Theory
Einstein's research after general relativity consisted primarily of a long series of attempts to generalize his theory of gravitation in order to unify and simplify the fundamental laws of physics, particularly gravitation and electromagnetism. In 1950, he described this "Unified Field Theory" in a Scientific American article entitled "On the Generalized Theory of Gravitation."
Although he continued to be lauded for his work in theoretical physics, Einstein became increasingly isolated in his research, and his attempts were ultimately unsuccessful. In his pursuit of a unification of the fundamental forces, he ignored mainstream developments in physics (and vice versa), most notably the strong and weak nuclear forces, which were not well understood until many years after Einstein's death. Einstein's goal of unifying the laws of physics under a single model survives in the current drive for the grand unification theory.
Collaboration and conflict
In 1924, Einstein received a statistical model from Indian physicist Satyendra Nath Bose which showed that light could be understood as a gas. Bose's statistics applied to some atoms as well as to the proposed light particles, and Einstein 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 should appear at very low temperatures. It was not until 1995 that the first such condensate was produced experimentally by Eric 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.
Subatomic particles divide into two classes: the bosons which obey Bose-Einstein probability statistics, and the fermions which do not, they obey Fermi-Dirac statistics. Neither is like familiar classical probability statistics. To give a sense of the difference, two classical coins have a 50-50 probability of coming up a pair (two heads or two tails), two boson coins have exactly 100 percent probability of coming up a pair, while two fermion coins have exactly zero probability of coming up a pair.
Schrödinger gas model
Einstein suggested to Erwin Schrödinger an application of Max Planck's idea of treating energy levels for a gas as a whole rather than for individual molecules, and Schrödinger applied this in a paper using the Boltzmann distribution to derive the thermodynamic properties of a semiclassical ideal gas. Schrödinger urged Einstein to add his name as co-author, although Einstein declined the invitation.
The Einstein refrigerator
In 1926, Einstein and his former student Leó Szilárd, a Hungarian physicist who later worked on the Manhattan Project and is credited with the discovery of the chain reaction, co-invented (and in 1930, patented) the Einstein refrigerator, revolutionary for having no moving parts and using only heat, not ice, as an input.
Bohr versus Einstein
In the 1920s, quantum mechanics developed into a more complete theory. Einstein was unhappy with the "Copenhagen interpretation" of quantum theory developed by Niels Bohr and Werner Heisenberg, wherein quantum phenomena are inherently probabilistic, with definite states resulting only upon interaction with classical systems. A public debate between Einstein and Bohr followed, lasting for many years (including during the Solvay Conferences). Einstein formulated gedanken experiments against the Copenhagen interpretation, which were all rebutted by Bohr. In a 1926 letter to Max Born, Einstein wrote: "I, at any rate, am convinced that He does not throw dice."
Einstein was never satisfied by what he perceived to be quantum theory's intrinsically incomplete description of nature, and in 1935 he further explored the issue in collaboration with Boris Podolsky and Nathan Rosen, noting that the theory seems to require non-local interactions; this is known as the EPR paradox. The EPR gedanken experiment has since been performed, with results confirming quantum theory's predictions.
Einstein's disagreement with Bohr revolved around the idea of scientific determinism. For this reason the repercussions of the Einstein-Bohr debate have found their way into philosophical discourse as well.
The question of scientific determinism gave rise to questions about Einstein's position on theological determinism, and even whether or not he believed in God. In 1929, Einstein told Rabbi Herbert S. Goldstein "I believe in Spinoza's God, who reveals Himself in the lawful harmony of the world, not in a God Who concerns Himself with the fate and the doings of mankind." In 1950, in a letter to M. Berkowitz, Einstein stated that "My position concerning God is that of an agnostic. I am convinced that a vivid consciousness of the primary importance of moral principles for the betterment and ennoblement of life does not need the idea of a law-giver, especially a law-giver who works on the basis of reward and punishment."
Einstein defined his religious views in a letter he wrote in response to those who claimed that he worshipped a Judeo-Christian god: "It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."
By his own definition, Einstein was a deeply religious person. He published a paper in Nature in 1940 entitled "Science and Religion" which gave his views on the subject. In this he says that: "a person who is religiously enlightened appears to me to be one who has, to the best of his ability, liberated himself from the fetters of his selfish desires and is preoccupied with thoughts, feelings and aspirations to which he clings because of their super-personal value … regardless of whether any attempt is made to unite this content with a Divine Being, for otherwise it would not be possible to count Buddha and Spinoza as religious personalities. Accordingly a religious person is devout in the sense that he has no doubt of the significance of those super-personal objects and goals which neither require nor are capable of rational foundation …. In this sense religion is the age-old endeavor of mankind to become clearly and completely conscious of these values and goals, and constantly to strengthen their effects." He argues that conflicts between science and religion "have all sprung from fatal errors." However "even though the realms of religion and science in themselves are clearly marked off from each other" there are "strong reciprocal relationships and dependencies" … "science without religion is lame, religion without science is blind … a legitimate conflict between science and religion cannot exist." However he makes it clear that he does not believe in a personal God, and suggests that "neither the rule of human nor Divine Will exists as an independent cause of natural events. To be sure, the doctrine of a personal God interfering with natural events could never be refuted … by science, for [it] can always take refuge in those domains in which scientific knowledge has not yet been able to set foot."
The most thorough exploration of Einstein's views on religion was made by his friend Max Jammer in the 1999 book Einstein and Religion.
Einstein was an Honorary Associate of the Rationalist Press Association beginning in 1934, and was an admirer of Ethical Culture. He served on the advisory board of the First Humanist Society of New York.
With increasing public demands, his involvement in political, humanitarian and academic projects in various countries and his new acquaintances with scholars and political figures from around the world, Einstein was less able to get the productive isolation that, according to biographer Ronald W. Clark, he needed in order to work. Due to his fame and genius, Einstein found himself called on to give conclusive judgments on matters that had nothing to do with theoretical physics or mathematics. He was not timid, and he was aware of the world around him, with no illusion that ignoring politics would make world events fade away. His very visible position allowed him to speak and write frankly, even provocatively, at a time when many people of conscience could only flee to the underground or keep doubts about developments within their own movements to themselves for fear of internecine fighting. Einstein flouted the ascendant Nazi movement, tried to be a voice of moderation in the tumultuous formation of the State of Israel and braved anti-communist politics and resistance to the civil rights movement in the United States. He became honorary president of the League against Imperialism created in Brussels in 1927.
Einstein was a cultural Zionist. In 1931, The Macmillan Company published About Zionism: Speeches and Lectures by Professor Albert Einstein. Querido, an Amsterdam publishing house, collected 11 of Einstein's essays into a 1933 book entitled Mein Weltbild, translated to English as The World as I See It; Einstein's foreword dedicates the collection "to the Jews of Germany." In the face of Germany's rising militarism Einstein wrote and spoke for peace.
Despite his years as a proponent of Jewish history and culture, Einstein publicly stated reservations about the proposal to partition the British-supervised British Mandate of Palestine into independent Arab and Jewish countries. In a 1938 speech, "Our Debt to Zionism," he said: "I am afraid of the inner damage Judaism will sustain - especially from the development of a narrow nationalism within our own ranks, against which we have already had to fight strongly, even without a Jewish state." The United Nations did divide the mandate, demarcating the borders of several new countries including the State of Israel, and war broke out immediately. Einstein was one of the authors of a 1948 letter to the New York Times criticizing Menachem Begin's Revisionist Herut (Freedom) Party for the Deir Yassin massacre. Einstein served on the Board of Governors of The Hebrew University of Jerusalem. In his Will of 1950, Einstein bequeathed literary rights to his writings to The Hebrew University, where many of his original documents are held in the Albert Einstein Archives.
When President Chaim Weizmann died in 1952, Einstein was asked to be Israel's second president but he declined. He wrote: "I am deeply moved by the offer from our State of Israel, and at once saddened and ashamed that I cannot accept it."
In January 1933, Adolf Hitler was elected Chancellor of Germany. One of the first actions of Hitler's administration was the "Gesetz zur Wiederherstellung des Berufsbeamtentums" (the Law for the Restoration of the Professional Civil Service) which removed Jews and politically suspect government employees (including university professors) from their jobs, unless they had demonstrated their loyalty to Germany by serving in World War I. In December 1932, in response to this growing threat, Einstein had prudently traveled to the USA. For several years he had been wintering at the California Institute of Technology in Pasadena, California, and also was a guest lecturer at Abraham Flexner's newly founded Institute for Advanced Study in Princeton, New Jersey.
The Einstein family bought a house in Princeton (where Elsa died in 1936), and Einstein remained an integral contributor to the Institute for Advanced Study until his death in 1955. During the 1930s and into World War II, Einstein wrote affidavits recommending United States visas for a huge number of Jews from Europe trying to flee persecution, raised money for Zionist organizations and was in part responsible for the formation, in 1933, of the International Rescue Committee.
Meanwhile in Germany, a campaign to eliminate Einstein's work from the German lexicon as unacceptable "Jewish physics" (Jüdische physik) was led by Nobel laureates Philipp Lenard and Johannes Stark. Deutsche Physik activists published pamphlets and even textbooks denigrating Einstein, and instructors who taught his theories were blacklisted, including Nobel laureate Werner Heisenberg who had debated quantum probability with Bohr and Einstein. Philipp Lenard claimed that the mass–energy equivalence formula needed to be credited to Friedrich Hasenöhrl to make it an Aryan creation.
Einstein became a citizen of the United States in 1940, although he retained his Swiss citizenship.
The atomic bomb
Concerned scientists, many of them refugees from European anti-Semitism in the U.S., recognized the possibility that German scientists were working toward developing an atomic bomb. They knew that Einstein's fame might make their fears more believable. In 1939, Leo Szilárd and Einstein wrote a letter to U.S. Pres. Franklin Delano Roosevelt warning that the Third Reich might be developing nuclear weapons based on their own research.
The United States took stock of this warning, and within five years, the U.S. created its own nuclear weapons, and used them to end the war with Japan, dropping them on the Japanese cities of Nagasaki and Hiroshima. According to chemist and author Linus Pauling, Einstein later expressed regret about the Szilárd-Einstein letter.
Along with other prominent individuals such as Eleanor Roosevelt and Henry Morgenthau, Jr., Einstein in 1947 participated in a "National Conference on the German Problem," which produced a declaration stating that "any plans to resurrect the economic and political power of Germany… [were] dangerous to the security of the world."
Cold War era
When he was a visible figure working against the rise of Nazism, Einstein had sought help and developed working relationships in both the West and what was to become the Soviet bloc. After World War II, enmity between the former allies became a very serious issue for people with international resumes. To make things worse, during the first days of McCarthyism Einstein was writing about a single world government; it was at this time that he wrote,
"I do not know how the third World War will be fought, but I can tell you what they will use in the Fourth—rocks!"
In a 1949 Monthly Review article entitled "Why Socialism?" Albert Einstein described a chaotic capitalist society, a source of evil to be overcome, as the "predatory phase of human development". With Albert Schweitzer and Bertrand Russell, Einstein lobbied to stop nuclear testing and future bombs. Days before his death, Einstein signed the Russell-Einstein Manifesto, which led to the Pugwash Conferences on Science and World Affairs.
Einstein was a member of several civil rights groups, including the Princeton chapter of the NAACP. When the aged W.E.B. DuBois was accused of being a communist spy, Einstein volunteered as a character witness and the case was dismissed shortly afterward. Einstein's friendship with activist Paul Robeson, with whom he served as co-chair of the American Crusade to End Lynching, lasted 20 years.
In 1946, Einstein collaborated with Rabbi Israel Goldstein, Middlesex heir C. Ruggles Smith, and activist attorney George Alpert on the Albert Einstein Foundation for Higher Learning, Inc., which was formed to create a Jewish-sponsored secular university, open to all students, on the grounds of the former Middlesex College in Waltham, Massachusetts. Middlesex was chosen in part because it was accessible from both Boston and New York City, Jewish cultural centers of the USA. Their vision was a university "deeply conscious both of the Hebraic tradition of Torah looking upon culture as a birthright, and of the American ideal of an educated democracy." The collaboration was stormy, however. Finally, when Einstein wanted to appoint British economist Harold J. Laski as the university's president, Alpert wrote that Laski was "a man utterly alien to American principles of democracy, tarred with the Communist brush." Einstein withdrew his support and barred the use of his name. The university opened in 1948 as Brandeis University. In 1953, Brandeis offered Einstein an honorary degree, but he declined.
Given Einstein's links to Germany and Zionism, his socialistic ideals, and his perceived links to Communist figures, the U.S. Federal Bureau of Investigation kept a file on Einstein that grew to 1,427 pages. Many of the documents in the file were sent to the FBI by concerned citizens, some objecting to his immigration while others asked the FBI to protect him.
Although Einstein had long been sympathetic to the notion of vegetarianism, it was only near the start of 1954 that he adopted a strict vegetarian diet.
On April 17, 1955, Albert Einstein experienced internal bleeding caused by the rupture of an aortic aneurysm. He took a 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 long enough to complete it. He died in Princeton Hospital early the next morning at the age of 76. Einstein's remains were cremated and his ashes were scattered.
Before the cremation, Princeton Hospital pathologist Thomas Stoltz Harvey removed Einstein's brain for preservation, in hope that the neuroscience of the future would be able to discover what made Einstein so intelligent.
While traveling, Einstein had written daily to his wife Elsa and adopted stepdaughters, Margot and Ilse, and the letters were included in the papers bequeathed to The Hebrew University. Margot Einstein permitted the personal letters to be made available to the public, but requested that it not be done until 20 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 3500 pages of private correspondence written between 1912 and 1955.
The United States' National Academy of Sciences commissioned the Albert Einstein Memorial, a monumental bronze and marble sculpture by Robert Berks, dedicated in 1979 at its Washington, D.C. campus adjacent to the National Mall.
Einstein bequeathed the royalties from use of his image to The Hebrew University of Jerusalem. The Roger Richman Agency licences the use of his name and associated imagery, as agent for the Hebrew University.
In 1999, Albert Einstein was named "Person of the Century" by TIME magazine, the Gallup Poll recorded him as the fourth most admired person of the twentieth century and according to "The 100: A Ranking of the Most Influential Persons in History," Einstein is "the greatest scientist of the twentieth century and one of the supreme intellects of all time."
A partial list of his memorials:
- The International Union of Pure and Applied Physics named 2005 the "World Year of Physics" in commemoration of the 100th anniversary of the publication of the Annus Mirabilis Papers.
- The Albert Einstein Memorial by Robert Berks
- A unit used in photochemistry, the einstein
- The chemical element 99, einsteinium
- The asteroid 2001 Einstein
- The Albert Einstein Award
- The Albert Einstein Peace Prize
- Einstein, Albert. Folgerungen aus den Capillaritätserscheinungen (Conclusions Drawn from the Phenomena of Capillarity). Annalen der Physik 4 (1901):513.
- Einstein, Albert. On a Heuristic Viewpoint Concerning the Production and Transformation of Light. Annalen der Physik 17 (1905):132–148.
- Einstein, Albert. A new determination of molecular dimensions. This Ph.D. thesis was completed April 30 and submitted July 20, 1905.
- Einstein, Albert. On the Motion—Required by the Molecular Kinetic Theory of Heat—of Small Particles Suspended in a Stationary Liquid. Annalen der Physik 17 (1905):549–560.
- Einstein, Albert. On the Electrodynamics of Moving Bodies. Annalen der Physik 17 (1905):891–921.
- Einstein, Albert. Does the Inertia of a Body Depend Upon Its Energy Content? Annalen der Physik 18 (1905):639–641.
- Einstein, Albert. Die Feldgleichungen der Gravitation (The Field Equations of Gravitation). Koniglich Preussische Akademie der Wissenschaften (1915): 844–847.
- Einstein, Albert. Kosmologische Betrachtungen zur allgemeinen Relativitätstheorie (Cosmological Considerations in the General Theory of Relativity). Koniglich Preussische Akademie der Wissenschaften (1917).
- Einstein, Albert. Zur Quantentheorie der Strahlung (On the Quantum Mechanics of Radiation). Physikalische Zeitschrift 18 (1917):121–128.
- Einstein, Albert. Fundamental Ideas and Problems of the Theory of Relativity. Nobel Lectures, Physics 1901–1921, 1923. Retrieved December 18, 2007.
- Einstein, Albert. Quantentheorie des einatomigen idealen Gases (Quantum theory of monatomic ideal gases). Sitzungsberichte der Preussichen Akademie der Wissenschaften Physikalisch—Mathematische Klasse (1924): 261–267.
- Einstein, Albert. Die Ursache der Mäanderbildung der Flussläufe und des sogenannten Baerschen Gesetzes. Die Naturwissenschaften (1926): 223-224.
- Einstein, Albert, Boris Podolsky, Nathan Rosen. Can Quantum-Mechanical Description of Physical Reality Be Considered Complete? Physical Review 47(10) (1935):777–780.
- Einstein, Albert. On Science and Religion. Nature 146 (1940).
- Einstein, Albert, et al. To the editors. The New York Times, 1948. Retrieved December 18, 2007.
- Einstein, Albert. Why Socialism?. Monthly Review, 1949. Retrieved December 18, 2007.
- Einstein, Albert. On the Generalized Theory of Gravitation. Scientific American CLXXXII(4) (1950):13–17.
- Einstein, Albert. Ideas and Opinions. New York, NY: Random House, 1954. ISBN 0517003937.
- Einstein, Albert. Albert Einstein, Hedwig und Max Born: Briefwechsel 1916–1955. Munich, DE: Nymphenburger Verlagshandlung, 1969.
- Einstein, Albert, Paul Arthur Schilpp, trans. Autobiographical Notes. Chicago, IL: Open Court, 1979. ISBN 0875483526.
- Thomas Sowell, The Einstein Syndrome: Bright Children Who Talk Late. (New York, NY: Basic Books, 2001, ISBN 0465081401).
- P. A. Schilpp, Albert Einstein - Autobiographical Notes. (Chicago, IL: Chicago University Press, 1979).
- Dudley Herschbach, HarvardChem-Einstein-PDF Einstein as a Student. Department of Chemistry and Chemical Biology, Harvard University. Retrieved December 17, 2007.
- Albert Einstein, Autobiographical Notes (Centennial ed.) (Chicago, IL: Open Court, 1979 ISBN 0875483526), 48–51. description of chasing a light beam thought experiment
- Collected papers Vol. 1, (document 134).
- Short life history: Lieserl Einstein-MaricEinstein website.
- Albert Einstein, Folgerungen aus den Capillaritätserscheinungen (Conclusions Drawn from the Phenomena of Capillarity). Annalen der Physik 4 (1901):513.
- Peter Galison, Einstein's Clocks: The Question of Time. Critical Inquiry 26(2) (2000):355–389.
- Peter Galison, Einstein's Clocks, Poincaré's Maps: Empires of Time. (New York, NY: W.W. Norton, 2003, ISBN 0393020010).
- Albert Einstein, On a Heuristic Viewpoint Concerning the Production and Transformation of Light. Annalen der Physik 17 (1905):132–148. This annus mirabilis paper on the photoelectric effect was received by Annalen der Physik March 18.
- Albert Einstein, On the Motion—Required by the Molecular Kinetic Theory of Heat—of Small Particles Suspended in a Stationary Liquid. Annalen der Physik 17 (1905):549–560. This annus mirabilis paper on Brownian motion was received May 11
- Albert Einstein, On the Electrodynamics of Moving Bodies. Annalen der Physik 17 (1905):891–921. This annus mirabilis paper on special relativity received June 30.
- Albert Einstein, Does the Inertia of a Body Depend Upon Its Energy Content? Annalen der Physik 18 (1905):639–641. This annus mirabilis paper on mass-energy equivalence was received September 27.
- Abraham Pais, Subtle is the Lord. The Science and the Life of Albert Einstein. (Oxford, UK: Oxford University Press, 1982, ISBN 0195204387).
- Thomas F. Glick, (ed.), The Comparative Reception of Relativity. (Boston, MA: D. Reidel, 1987 ISBN 9027724989).
- Albert Einstein, "A new determination of molecular dimensions." This Ph.D. thesis was completed April 30 and submitted July 20, 1905.
- Thomas Levenson, "Genius Among Geniuses, Einstein's Big Idea." Public Broadcasting Service, 2005.
- Albert Einstein, On the Influence of Gravity on the Propagation of Light. Annalen der Physik 35 (1911):898–908.
- Jeffrey Crelinsten, Einstein's Jury: The Race to Test Relativity. (Princeton, NJ: Princeton University Press, 2006, ISBN 978-0691123103).
- Albert Einstein, Die Feldgleichungen der Gravitation (The Field Equations of Gravitation). Koniglich Preussische Akademie der Wissenschaften (1915): 844–847.
- Horst Kant, "Albert Einstein and the Kaiser Wilhelm Institute for Physics in Berlin," in Jürgen Renn, Albert Einstein - Chief Engineer of the Universe: One Hundred Authors for Einstein (Hoboken, NJ: Wiley-VCH, 2005, ISBN 3527405747).
- Jeffrey Crelinsten, Einstein's Jury: The Race to Test Relativity. (Princeton, NJ: Princeton University Press, 2006, ISBN 978-0691123103).
- Myths in science. EMBO reports 4(3):236. Retrieved December 17, 2007.
- Jürgen Schmidhuber, Albert Einstein (1879–1955) and the "Greatest Scientific Discovery Ever. IDSIA, 2006. Retrieved December 21, 2007.
- Bending Light. Math Pages. Retrieved December 17, 2007.
- Klaus Hentschel, & Ann M. Hentschel, Physics and National Socialism: An Anthology of Primary Sources. (Boston, MA: Birkhaeuser Verlag, 1996, ISBN 3764353120).
- Albert Einstein. Fundamental Ideas and Problems of the Theory of Relativity, Nobel Lectures, Physics 1901–1921, (Amsterdam: Elsevier Publishing Company, 1923).
- Albert Einstein, Ideas and Opinions. (New York, NY: Random House, 1954, ISBN 0517003937).
- Albert Einstein, On the Generalized Theory of Gravitation. Scientific American CLXXXII (4) (1950):13–17.
- Albert Einstein, Quantentheorie des einatomigen idealen Gases (Quantum theory of monatomic ideal gases). Sitzungsberichte der Preussichen Akademie der Wissenschaften Physikalisch—Mathematische Klasse. (1924):261–267.
- Instituut-Lorentz, Einstein archive at the Instituut-Lorentz, 2005.
- Walter Moore, Schrödinger: Life and Thought. (Cambridge, UK: Cambridge University Press, 1989, ISBN 0521437679).
- Gary Goettling, "Einstein's Refrigerator," Georgia Tech Alumni Magazine Online, Georgia Tech Alumni Association, 1998.
- Albert Einstein. Albert Einstein, Hedwig und Max Born: Briefwechsel 1916–1955. (Munich, DE: Nymphenburger Verlagshandlung, 1969).
- Alain Aspect, Jean Dalibard, Gérard Roger, Experimental test of Bell's inequalities using time-varying analyzers. Physical Review Letters 49(25) (1982):1804-1807.
- Dennis Brian, Einstein: A Life. (Hoboken, NJ: John Wiley & Sons, 1996, ISBN 0471114596).
- Alice Calaprice, (ed.) The Expanded Quotable Einstein. (Princeton, NJ: Princeton University Press, 2000, ISBN 0691120749).
- Helen Dukas and Banesh Hoffman, (eds.) Albert Einstein, The Human Side. (Princeton, NJ: Princeton University Press, 1981 ISBN 0691082316).
- Abraham Pais, Subtle is the Lord. The Science and the Life of Albert Einstein. (Oxford, UK: Oxford University Press, 1982, ISBN 0195204387).
- Albert Einstein, "Science and Religion." Nature 146 (1940):605–607.
- Hervé Toulhoat, Paul Diel, pionnier de la psychologie des profondeurs et Albert Einstein. Chimie Paris 315 (2006):12–15.
- Paul Diel, The God-Symbol: Its History and its Significance. (San Francisco, CA: Harper & Row, 1986, ISBN 0062548050).
- Max Jammer, Einstein and Religion. (Princeton, NJ: Princeton University Press, 1999, ISBN 0691006997).
- Ronald W. Clark, Einstein: The Life and Times (New York, NY: Avon Books, 1971, ISBN 0380441233).
- American Museum of Natural History, "Einstein's Revolution," 2002.
- David E. Rowe & Robert Schulmann, Einstein on Politics: His Private Thoughts and Public Stands on Nationalism, Zionism, War, Peace, and the Bomb. (Princeton, NJ: Princeton University Press, 2007, ISBN 0691120943).
- Albert Einstein et al., To the editors. The New York Times, 1948.
- Einstein Archives Online Retrieved December 18, 2007.
- Albert Einstein Museum. Princeton History. Retrieved December 18, 2007.
- R. Clark, Einstein: The Life and Times. (New York, NY: H.N. Abrams, 1984, ISBN 0810908751).
- Official Website. International Rescue Committee. Retrieved December 17, 2007.
- Steven Casey, The campaign to sell a harsh peace for Germany to the American public, 1944–1948. History 90(297) (2005):62–92.
- Alice Calaprice, The New quotable Einstein. (Princeton, NJ: Princeton University Press, 2005, ISBN 0691120757).
- Albert Einstein, Why Socialism? Monthly Review, 1949.
- Arthur H. Reis, Jr., The Albert Einstein Involvement. Brandeis Review, 50th Anniversary Edition, 1998.
- Dr. Einstein Quits University Plan. The New York Times.
- "Albert Einstein." FBI Freedom of Information Act Website. U.S. Federal Government, U.S. Department of Justice.
- Einstein Archives Online. Retrieved December 18, 2007.
- J.J. O'Connor & E.F. Robertson, "Albert Einstein," The MacTutor History of Mathematics archive, School of Mathematics and Statistics, University of St. Andrews, 1997.
- Obituary. The New York Times. Retrieved December 17, 2007.
- Letters reveal Einstein love life. BBC News. Retrieved December 18, 2007.
- Albert Einstein Licensing Program. Albert Einstein.net. Retrieved December 18, 2007.
- Person of the Century: Albert Einstein. TIME. Retrieved December 18, 2007.
- Hart 1978
- Beck, Anna. The Collected Papers of Albert Einstein, Volume 1: The Early Years, 1879–1902. (English translation supplement). Princeton, NJ: Princeton University Press, 1987. ISBN 978-0691084756.
- Bodanis, David. Einstein's Big Idea. Public Broadcasting Service, 2005. Retrieved December 18, 2007.
- Bolles, Edmund Blair. Einstein Defiant: Genius versus Genius in the Quantum Revolution. Washington, DC: Joseph Henry Press, 2004. ISBN 0309089980.
- Brian, Dennis. Einstein: A Life. Hoboken, NJ: John Wiley & Sons, 1996. ISBN 0471114596.
- Butcher, Sandra Ionno. The Origins of the Russell-Einstein Manifesto. Pugwash History Series, 2005. Retrieved December 18, 2007.
- Calaprice, Alice. The New quotable Einstein. Princeton, NJ: Princeton University Press, 2005. ISBN 0691120757.
- Clark, Ronald W. Einstein: The Life and Times. New York, NY: Avon, 1971. ISBN 0380441233.
- Crelinsten, Jeffrey. Einstein's Jury: The Race to Test Relativity. Princeton, NJ: Princeton University Press, 2006. ISBN 978-0691123103.
- Ericson, Edward L. The Humanist Way: An Introduction to Ethical Humanist Religion. American Ethical Union, 2006. Retrieved December 18, 2007.
- Esterson, Allen. Mileva Marić: Einstein's Wife. Esterson.org. Retrieved December 18, 2007.
- Galison. Peter. Einstein's Clocks: The Question of Time. Critical Inquiry. 26(2) (2000):355–389.
- Goettling, Gary. Einstein's Refrigerator. Georgia Tech Alumni Magazine Online, 1998. Retrieved December 18, 2007.
- Golden, Frederic. Person of the Century: Albert Einstein. TIME, 2000. Retrieved December 18, 2007.
- Hart, Michael H. The 100: A Ranking of the Most Influential Persons in History. New York, NY: Hart Pub. Co., 1978. ISBN 0806513500.
- Hentschel, Klaus, Ann M. Hentschel. Physics and National Socialism: An Anthology of Primary Sources. Boston, MA: Birkhaeuser Verlag, 1996. ISBN 3764353120.
- Herschbach, Dudley. Einstein as a Student. Harvard Chemistry Dept., 2005. Retrieved December 18, 2007.
- Highfield, Roger, and Paul Carter. The Private Lives of Albert Einstein. Boston, MA: Faber and Faber, 1993. ISBN 0312110472.
- Holt, Jim. Time Bandits. The New Yorker, 2005. Retrieved December 21, 2007.
- Isaacson, Walter. Einstein: His Life and Universe. New York, NY: Simon & Schuster, 2007. ISBN 978-0743264730.
- Isaacson, Walter. Person of the Century: Why We Chose Einstein. TIME, 2000. Retrieved December 21, 2007.
- Jammer, Max. Einstein and Religion. Princeton, NJ: Princeton University Press, 1999. ISBN 0691006997.
- Kant, Horst, and Jürgen Renn, (eds.). Albert Einstein - Chief Engineer of the Universe: One Hundred Authors for Einstein. Hoboken, NJ: Wiley-VCH, 2005. ISBN 3527405747.
- Kupper, Hans-Josef. Various things about Albert Einstein. Einstein Website, 2000. Retrieved December 21, 2007.
- Levenson, Thomas. "Genius Among Geniuses" : Einstein's Big Idea. Public Broadcasting Service, 2005. Retrieved December 21, 2007.
- Levitt, Dan. Brilliant Minds: Secrets of the Cosmos. Boston, MA: Veriscope Pictures, 2003.
- Martínez, Alberto A. Arguing about Einstein's wife. Physics World, 2004. Retrieved December 21, 2007.
- Mehra, Jagdish. The Golden Age of Theoretical Physics. River Edge, NJ: World Scientific, 2001. ISBN 978-9810243425.
- Pais, Abraham. Subtle is the Lord. The Science and the Life of Albert Einstein. Oxford, UK: Oxford University Press, 1982. ISBN 0195204387.
- Pais, Abraham. Einstein Lived Here. Oxford, UK: Oxford University Press, 1994. ISBN 0198539940.
- Pickover, Clifford A. Sex, Drugs, Einstein, and Elves: Sushi, Psychedelics, Parallel Universes, and the Quest for Transcendence. Petaluma, CA: Smart Publications, 2005. ISBN 1890572179.
- Renn, Jürgen. Albert Einstein - Chief Engineer of the Universe: One Hundred Authors for Einstein. Hoboken, NJ: Wiley-VCH, 2005. ISBN 3527405747.
- Renn, Jürgen. Albert Einstein - Chief Engineer of the Universe: Einstein's Life and Work in Context and Documents of a Life's Pathway. Hoboken, NJ: Wiley-VCH, 2006. ISBN 3527405712.
- Robinson, Andrew. Einstein: A Hundred Years of Relativity. New York, NY: Harry N. Abrams, 2005. ISBN 0954510348.
- Rosenkranz, Ze'ev. Albert Einstein—Derrière l'image. Zurich: Editions NZZ, 2005. ISBN 3038231827.
- Rowe, David E., Robert Schulmann. Einstein on Politics: His Private Thoughts and Public Stands on Nationalism, Zionism, War, Peace, and the Bomb. Princeton, NJ: Princeton University Press, 2007. ISBN 0691120943.
- Smith, Peter D. Einstein (Life & Times Series). London, UK: Haus Publishing, 2000. ISBN 1904341152.
- Sowell, Thomas. The Einstein Syndrome: Bright Children Who Talk Late. New York, NY: Basic Books, 2001. ISBN 0465081401.
- Stachel, John, H.M. Pycior, N.G. Slack, P.G. Abir-Am (eds.). "Albert Einstein and Mileva Maric: A Collaboration That Failed to Develop." Creative Couples in the Sciences. New Brunswick, NJ: Rutgers University Press, 1996. ISBN 0813521882.
- Stachel, John. Einstein's Miraculous Year: Five Papers That Changed the Face of Physics. Princeton, NJ: Princeton University Press, 1998. ISBN 0691059381.
- Stachel, John, Martin J. Klein, A. J. Kox, Michel Janssen, R. Schulmann, Diana Komos Buchwald and others, (eds.). The Collected Papers of Albert Einstein, Vol 1–10. Princeton, NJ: Princeton University Press, 1987–2006.
- Stern, Fritz. Einstein's German World. Princeton, NJ: Princeton University Press, 1999. ISBN 069105939X.
- Thorne, Kip. Black Holes and Time Warps|Black Holes and Time Warps: Einstein's Outrageous Legacy. New York, NY: W.W. Norton & Company, 1995. ISBN 0393312763.
- Zackheim, Michele. Einstein's Daughter: the Search for Lieserl. New York, NY: Riverhead Books, 1999. ISBN 1573221279.
All links retrieved May 10, 2021.
- Einstein Thought Experiments
- Works by Albert Einstein. Project Gutenberg (complete texts, downloadable, no charge).
- "A. Einstein: Image and Impact", on the American Institute of Physics's "AIP Center for the History of Physics" site: biography, audio and full site as downloadable PDF for classroom use.
- "The MacTutor History of Mathematics archive": Albert Einstein University of Saint Andrews, School of Mathematics and Statistics.
- "Einstein's Big Idea" NOVA television documentary series website, Public Broadcasting Service (can watch a preview online).
- Official site of the International Rescue Committee
- Einstein Papers Project. Caltech.
- Albert Einstein (1879–1955) and the "Greatest Scientific Discovery Ever"
- Albert Einstein - Biography. Nobel Lectures, Physics 1901–1921.
- The Nobel Prize in Physics 1921. Nobel Foundation.
- Dr. Einstein Quits University Plan. The New York Times.
- Einstein archive at the Instituut-Lorentz. Instituut-Lorentz.
- Letters Reveal Einstein Love Life. BBC News.
|Notable teachers||Notable students|
|Alfred Kleiner||Hans Tanner|
New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:
The history of this article since it was imported to New World Encyclopedia:
Note: Some restrictions may apply to use of individual images which are separately licensed.