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Albert Einstein

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Jason
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« on: August 24, 2007, 01:08:21 pm »



Photographed by Oren J. Turner (1947)
Born March 14, 1879(1879-03-14)
Ulm, Württemberg, Germany
Died April 18, 1955 (aged 76)
Princeton, New Jersey, USA
Residence Germany, Italy, Switzerland, USA
Citizenship German (1879–96, 1914–33)
Swiss (1901–55)
American (1940–55)
Ethnicity Jewish
Field Physics
Institutions Swiss Patent Office (Berne)
Univ. of Zürich
Charles Univ.
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
Special relativity
Brownian motion
Photoelectric effect
Mass-energy equivalence
Einstein field equations
Unified Field Theory
Bose–Einstein statistics
EPR paradox
Notable prizes  Nobel Prize in Physics (1921)
Copley Medal (1925)
Max Planck medal (1929)
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« Reply #1 on: August 24, 2007, 01:09:45 pm »

Best known for his theory of relativity and specifically mass-energy equivalence, E = mc2. 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.

Works by Albert Einstein include more than fifty 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.
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« Reply #2 on: August 24, 2007, 01:11:18 pm »



Albert Einstein in 1893 (age 14), taken before the family moved to Italy.
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 (Rosenkranz 2005, p. 29).

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.

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« Reply #3 on: August 24, 2007, 01:13:00 pm »

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 twelve, 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 fifteen, 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 (Einstein 1979).

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". Einstein and Marić had a daughter, Lieserl Einstein, born in early 1902. Her fate is unknown.

In 1900, 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 (Einstein 1901). He graduated from ETH with a teaching diploma.

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« Reply #4 on: August 24, 2007, 01:13:58 pm »



The 'Einsteinhaus' in Bern where Einstein lived with Mileva on the first floor during his Annus Mirabilis
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« Reply #5 on: August 24, 2007, 01:15:17 pm »

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. Einstein occasionally corrected design errors while evaluating patent applications. 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.

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« Reply #6 on: August 24, 2007, 01:17:41 pm »



Albert Einstein, 1905

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". (Einstein 1905a)
•   His paper on Brownian motion explained the random movement of very small objects as direct evidence of molecular action, thus supporting the atomic theory. (Einstein 1905c)
•   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. (Einstein 1905d)
•   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: E = mc2, suggesting that tiny amounts of mass could be converted into huge amounts of energy. (Einstein 1905e)
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.[23] (Pais 1982, pp. 382–386)
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." (Einstein 1905b)
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« Reply #7 on: August 24, 2007, 01:18:54 pm »



One of the 1919 eclipse photographs taken during Arthur Eddington's expedition, which confirmed Einstein's predictions of the gravitational bending of light.
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« Reply #8 on: August 24, 2007, 01:20:50 pm »

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 (Pais 1982, p. 522). 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 (Levenson 2005).

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 (Crelinsten 2006).

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 (Einstein 1915). 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 (Kant 2005).

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 (Einstein 1917b). 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 (Einstein 1917a).

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 (Crelinsten 2006, pp. 103–108). In 1918, the Lick Observatory, also in California, announced that they too had disproven Einstein's prediction, although their findings were not published (Crelinsten 2006, pp. 114–119, 126–140).

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 (Crelinsten 2006). 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" (Schmidhuber 2006).

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 (Hentschel & Hentschel 1996, p. xxi).

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.

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« Reply #9 on: August 24, 2007, 01:23:41 pm »



Einstein, 1921. Age 42.

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." (Einstein 1923)

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 (Einstein 1954)
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« Reply #10 on: August 24, 2007, 01:25:23 pm »



Max Planck presents Einstein with the inaugural Max Planck medal, Berlin June 28, 1929

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" (Einstein 1950).

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.
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« Reply #11 on: August 24, 2007, 01:26:45 pm »

Collaboration and conflict

Bose–Einstein statistics

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 (Einstein 1924). 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 (Instituut-Lorentz 2005).

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« Reply #12 on: August 24, 2007, 01:28:01 pm »

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 (Goettling 1998).
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« Reply #13 on: August 24, 2007, 01:30:01 pm »



Einstein and Niels Bohr. Photo taken by Paul Ehrenfest during their visit to Leiden in December 1925.

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 1969).

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 (Einstein 1935). 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.

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« Reply #14 on: August 24, 2007, 01:32:11 pm »

Religious views

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." (Brian 1996, p. 127) 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 (Pais 1982, p. 319). 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 endeavour 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." (Einstein 1940, pp. 605–607)

Einstein championed the work of psychologist Paul Diel, which posited a biological and psychological, rather than theological or sociological, basis for morality.

The most thorough exploration of Einstein's views on religion was made by his friend Max Jammer in the 1999 book Einstein and Religion (Jammer 1999).

Einstein was an Honorary Associate of the Rationalist Press Association beginning in 1934, and was an admirer of Ethical Culture (Ericson 2006). He served on the advisory board of the First Humanist Society of New York (See Stringer-Hye 1999 and Wilson 1995).
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