Richard Phillips Feynman (May 11, 1918 – February 15, 1988) was an American theoretical physicist known for his work in the path integral formulations of quantum mechanics, the theory of quantum electrodynamics, and the physics of superfluidity of supercooled liquid helium, as well as in particle physics (he proposed the parton model). For his contributions to the development of quantum electrodynamics, Feynman, jointly with Julian Schwinger and Sin-Itiro Tomonaga, received the Nobel Prize in Physics in 1965. He developed a widely used pictorial representation scheme for the mathematical expressions governing the behavior of subatomic particles, which later became known as Feynman diagrams. During his lifetime, Feynman became one of the best-known scientists in the world. In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World he was ranked as one of the ten greatest physicists of all time.
He assisted in the development of the atomic bomb and was a member of the panel that investigated the Space Shuttle Challenger disaster. In addition to his work in theoretical physics, Feynman has been credited with pioneering the field of quantum computing and introducing the concept of nanotechnology. He held the Richard Chace Tolman professorship in theoretical physics at the California Institute of Technology.
In high school, his IQ was determined to be 125—high, but "merely respectable" according to biographer James Gleick. Feynman later scoffed at psychometric testing. In the year 1933, in which he turned 15, he taught himself trigonometry, advanced algebra, infinite series, analytic geometry and both differential and integral calculus. Before entering college, he was experimenting with and re-creating mathematical topics, such as the half-derivative, using his own notation. In high school, he was developing the mathematical intuition behind his Taylof series of mathematical operators.
His habit of direct characterization sometimes rattled more conventional thinkers; for example, one of his questions, when learning feline anatomy, was "Do you have a map of the cat?" (referring to an anatomical chart).
Feynman attended Far Rockaway High School, a school also attended by fellow laureates Burton Richter and Baruch Samuel Blumberg. A member of the Arista Honor Society, in his last year in high school, Feynman won the New York University Math Championship; the large difference between his score and those of his closest competitors shocked the judges.
He applied to Columbia University, but was not accepted. Instead he attended the Massachusetts Institute of Technology, where he received a bachelor’s degree in 1939, and in the same year was named a Putnam Fellow. While there, Feynman took every physics course offered, including a graduate course on theoretical physics while only in his second year.
He obtained a perfect score on the graduate school entrance exams to Princeton University in mathematics and physics—an unprecedented feat—but did rather poorly on the history and English portions. Attendees at Feynman's first seminar included Albert Einstein, Wolfgang Pauli, and John von Neumann. He received a PhD. from Princeton in 1942; his thesis advisor was John Archibald Wheeler. Feynman's thesis applied the principle of stationary action to problems of quantum mechanics, inspired by a desire to quantize the Wheeler-Feynman absorber theory of electrodynamics, laying the groundwork for the "path integral" approach and Feynman diagrams, and was titled "The Principle of Least Action in Quantum Mechanics".
At Princeton, the physicist Robert R. Wilson encouraged Feynman to participate in the Manhattan Project — the wartime U.S. Army project at Los Alamos developing the atomic bomb. Feynman said he was persuaded to join this effort to build it before Nazi Germany developed their own bomb.
Feynman was sought out by physicist Niels Bohr for one-on-one discussions. He later discovered the reason: most of the other physicists were too in awe of Bohr to argue with him. Feynman had no such inhibitions, vigorously pointing out anything he considered to be flawed in Bohr's thinking. Feynman said he felt as much respect for Bohr as anyone else, but once anyone got him talking about physics, he would become so focused he forgot about social niceties.
Due to the top secret nature of the work, Los Alamos was isolated. In Feynman's own words, "There wasn't anything to do there". Bored, he indulged his curiosity by learning to pick the combination locks on cabinets and desks used to secure papers. Feynman played many jokes on colleagues. In one case he found the combination to a locked filing cabinet by trying the numbers he thought a physicist would use (it proved to be 27–18–28 after the base of natural logarithms, e = 2.71828…), and found that the three filing cabinets where a colleague kept a set of atomic bomb research notes all had the same combination. He left a series of notes in the cabinets as a prank, which initially spooked his colleague, Frederic de Hoffmann, into thinking a spy or saboteur had gained access to atomic bomb secrets. On several occasions, Feynman drove to Albuquerque to see his ailing wife in a car borrowed from Klaus Fuchs, who later was discovered to be a \
real spy for the Soviets, transporting nuclear secrets in his car to Santa Fe.
On occasion, Feynman would find an isolated section of the mesa where he could drum in the style of American natives; "and maybe I would dance and chant, a little". These antics did not go unnoticed, and rumors spread about a mysterious Indian drummer called "Injun Joe". He also became a friend of the laboratory head, J. Robert Oppenheimer, who unsuccessfully tried to court him away from his other commitments after the war to work at the University of California, Berkeley..
During a temporary depression following the destruction of Hiroshima by the bomb produced by the Manhattan Project, he focused on complex physics problems, not for utility, but for self-satisfaction. One of these was analyzing the physics of a twirling, nutating dish as it is moving through the air. His work during this period, which used equations of rotation to express various spinning speeds, soon proved important to his Nobel Prize-winning work. Yet because he felt burned out and had turned his attention to less immediately practical, but more entertaining, problems, he felt surprised by the offers of professorships from other renowned universities.
Despite yet another offer from the Institute for Advanced Study, Feynman rejected the Institute on the grounds that there were no teaching duties: Feynman felt that students were a source of inspiration and teaching was a diversion during uncreative spells. Because of this, the Institute for Advanced Study and Princeton University jointly offered him a package whereby he could teach at the university and also be at the institute. Feynman instead accepted an offer from the California Institute of Technology (Caltech) -- and as he says in his book Surely You're Joking Mr. Feynman! — because a desire to live in a mild climate had firmly fixed itself in his mind while he was installing tire chains on his car in the middle of a snowstorm in Ithaca.
Feynman has been called the "Great Explainer". He gained a reputation for taking great care when giving explanations to his students and for making it a moral duty to make the topic accessible. His guiding principle was that, if a topic could not be explained in a freshman lecture, it was not yet fully understood. Feynman gained great pleasure from coming up with such a "freshman-level" explanation, for example, of the connection between spin and statistics. What he said was that groups of particles with spin ½ "repel", whereas groups with integer spin "clump." This was a brilliantly simplified way of demonstrating how Fermi-Dirac statistics and Bose-Einsein statistics evolved as a consequence of studying how fermions and bosons behave under a rotation of 360°. This was also a question he pondered in his more advanced lectures, and to which he demonstrated the solution in the 1986 Dirac memorial lecture. In the same lecture, he further explained that antiparticles must exist, for if particles had only positive energies, they would not be restricted to a so-called "light cone."
He opposed rote learning or unthinking memorization and other teaching methods that emphasized form over function. He put these opinions into action whenever he could, from a conference on education in Brazil to a State Commission on school textbook selection. Clear thinking and clear presentation were fundamental prerequisites for his attention. It could be perilous even to approach him when unprepared, and he did not forget the fools or pretenders.
Feynman played an important role on the Presidential Rogers Commission, which investigated the Challenger disaster. During a televised hearing, Feynman demonstrated that the material used in the shuttle's O-rings became less resilient in cold weather by compressing a sample of the material in a clamp and immersing it in ice-cold water. The commission ultimately determined that the disaster was caused by the primary O-ring not properly sealing due to extremely cold weather at Cape Canaveral.
Feynman devoted the latter half of his book What Do You Care What Other People Think? to his experience on the Rogers Commission, straying from his usual convention of brief, light-hearted anecdotes to deliver an extended and sober narrative. Feynman's account reveals a disconnect between NASA’s engineers and executives that was far more striking than he expected. His interviews of NASA's high-ranking managers revealed startling misunderstandings of elementary concepts. For instance, NASA managers claimed that there was a 1 in 100,000 chance of a catastrophic failure aboard the shuttle, but Feynman discovered that NASA's own engineers estimated the chance of a catastrophe at closer to 1 in 100. He concluded that the space shuttle reliability estimate by NASA management was fantastically unrealistic, and he was particularly angered that NASA used these figures to recruit Christa McAuliffe into the Teacher-in-Space program. He warned in his appendix to the commission's report (which was included only after he threatened not to sign the report), "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." He also rebuked some mathematicians for their exclusivity, saying "I have great suspicion that [mathematicians] don't know that this stuff is wrong and that they're intimidating people."
Feynman had a great deal of success teaching Carl, using, for example, discussions about ants and Martians as a device for gaining perspective on problems and issues. He was surprised to learn that the same teaching devices were not useful with [his daughter,] Michelle. Mathematics was a common interest for father and son; they both entered the computer field as consultants and were involved in advancing a new method of using multiple computers to solve complex problems—later known as parallel computing. The Jet Propulsion Laboratory retained Feynman as a computational consultant during critical missions.
In addition, he had some degree of synesthesia for equations, explaining that the letters in certain mathematical functions appeared in color for him, even though invariably printed in standard black-and-white.
http://en.wikipedia.org/wiki/Richard_Feynman
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Footnote
"Anyone who claims to understand quantum theory is either lying or crazy," physicist Richard Feynman once said, according to legend.
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