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Richard Feynman

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   CAPTION: Richard P. Feynman

   "What I cannot create, I do not understand" —Richard P. Feynman
   "What I cannot create, I do not understand" —Richard P. Feynman
   Born May 11, 1918
   Queens, New York
   Died February 15, 1988
   Los Angeles, California
   Residence USA
   Nationality American
   Field Physics
   Institution Manhattan Project
   Cornell
   Caltech
   Alma Mater MIT
   Princeton
   Doctoral Advisor John Archibald Wheeler
   Doctoral Students Al Hibbs
   George Zweig
   Known for Quantum electrodynamics
   Particle theory
   Feynman diagrams
   Notable Prizes Nobel Prize in Physics (1965)
   Oersted Medal (1972)
   Religion Atheist

   Richard Phillips Feynman ( May 11, 1918 – February 15, 1988; surname
   pronounced FINE-man; /ˈfaɪnmən/) was an American physicist known for
   expanding the theory of quantum electrodynamics, the physics of the
   superfluidity of supercooled liquid helium, and particle theory. For
   his work on quantum electrodynamics, Feynman was a joint recipient of
   the Nobel Prize in Physics in 1965, together with Julian Schwinger and
   Shin-Ichiro Tomonaga; he developed a way to understand the behaviour of
   subatomic particles using pictorial tools that later became known as
   Feynman diagrams.

   He assisted in the development of the atomic bomb and was a member of
   the panel that investigated the Space Shuttle Challenger disaster.
   Despite his prolific contributions, Feynman wrote only 37 research
   papers during his career. In addition to his work in pure physics,
   Feynman is credited with the concept and early exploration of quantum
   computing, and publicly envisioning nanotechnology, creation of devices
   at the molecular scale. He held the Richard Chace Tolman professorship
   in theoretical physics at Caltech.

   Feynman was a keen and influential popularizer of physics in both his
   books and lectures, notably a seminal 1959 talk on top-down
   nanotechnology called There's Plenty of Room at the Bottom and The
   Feynman Lectures on Physics, a three-volume set which has become a
   classic text. Known for his insatiable curiosity, wit, brilliant mind
   and playful temperament, he is equally famous for his many adventures,
   detailed in his books Surely You're Joking, Mr. Feynman!, What Do You
   Care What Other People Think? and Tuva or Bust!. As well as being an
   inspirational lecturer, bongo player, notorious practical joker, and
   decipherer of Maya hieroglyphs, Richard Feynman was regarded as an
   eccentric and a free spirit. He liked to pursue multiple independent
   paths, such as biology, art, percussion, and lockpicking. Freeman Dyson
   once wrote that Feynman was "half-genius, half-buffoon", but later
   revised this to "all-genius, all-buffoon".

Biography

   Richard Phillips Feynman was born on 11 May 1918, in Far Rockaway,
   Queens, New York; his parents were Jewish and attended synagogue every
   Friday, although they were not ritualistic in their practice of
   Judaism. Feynman (in common with other famous physicists, Edward Teller
   and Albert Einstein) was a late talker; by his third birthday he had
   yet to utter a single word. The young Feynman was heavily influenced by
   his father, Melville, who encouraged him to ask questions to challenge
   orthodox thinking. From his mother he gained the sense of humor that
   endured throughout his life. His sister Joan also became a professional
   physicist. As a child, he delighted in repairing radios and had a
   talent for engineering.

Education

   In high school he was bright, with a measured IQ of 125: quite high,
   but lower than what is normally expected of a theoretical physicist. He
   would later scoff at psychometric testing. By 15, he had mastered
   differential and integral calculus. Before entering college, he was
   already experimenting with and re-creating mathematical topics, such as
   the half-derivative, utilizing his own notation. Thus, even while still
   in high school, he was developing the mathematical intuition behind his
   Taylor series of mathematical operators. His habit of direct
   characterization would sometimes disconcert 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).

   In his last year at Far Rockaway High School, Feynman won the New York
   University Math Championship. He applied to Columbia College, but was
   rejected because of its Jewish quota. Instead, he attended the
   Massachusetts Institute of Technology, where he received a bachelor's
   degree in 1939, and in the same year was named Putnam Fellow. While
   there, Feynman had taken every physics course offered, taking a
   graduate course on theoretical physics while only in his second year.
   He obtained a perfect score on the 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 the luminaries Albert Einstein,
   Wolfgang Pauli, and John von Neumann. He received a Ph.D. from
   Princeton University in 1942; his thesis advisor was John Archibald
   Wheeler. Feynman's thesis applied the principle of stationary action to
   problems of quantum mechanics, laying the ground work for the "path
   integral" approach and Feynman diagrams.

     This was Richard Feynman nearing the crest of his powers. At
     twenty-three ... there was no physicist on earth who could match his
     exuberant command over the native materials of theoretical science.
     It was not just a facility at mathematics (though it had become
     clear ... that the mathematical machinery emerging from the
     Wheeler-Feynman collaboration was beyond Wheeler's own ability).
     Feynman seemed to possess a frightening ease with the substance
     behind the equations, like Albert Einstein at the same age, like the
     Soviet physicist Lev Landau - but few others.

     —James Gleick , Genius: The Life and Science of Richard Feynman

   While researching his PhD, Feynman married his first wife, Arline
   Greenbaum. (Arline's name is often spelled Arlene). Arline was
   diagnosed with tuberculosis, a terminal illness at that time, but she
   and Feynman were careful, and he never contracted the disease.

The Manhattan Project

   Feynman (center) with Robert Oppenheimer (right) relaxing at a Los
   Alamos social function during the top-secret Manhattan Project.
   Enlarge
   Feynman (centre) with Robert Oppenheimer (right) relaxing at a Los
   Alamos social function during the top-secret Manhattan Project.

   At Princeton, the physicist Robert R. Wilson encouraged Feynman to
   participate in the Manhattan Project—the wartime U.S. Army project at
   Los Alamos attempting to develop the atomic bomb. Feynman said he was
   persuaded to join this effort to help make sure that Nazi Germany did
   not build it first. He was assigned to Hans Bethe's theoretical
   division, and impressed Bethe enough to be made a group leader.
   Together with Bethe, he developed the Bethe-Feynman formula for
   calculating the yield of a fission bomb, which built upon previous work
   by Robert Serber. Up until her death on June 16, 1945, he visited his
   wife in a sanatorium in Albuquerque each weekend. He immersed himself
   in work on the project, and was present at the Trinity bomb test.
   Feynman claimed to be the only person to see the explosion without the
   very dark glasses provided, reasoning that it was safe to ignore
   instructions and look through a truck windshield as it would screen out
   the harmful ultraviolet radiation.

   As a junior physicist, he was not central to the project; the greater
   part of his work consisted of administering the computation group of
   human computers in the Theoretical division, and later, with Nicholas
   Metropolis, setting up the system for using IBM punch cards for
   computation. Feynman succeeded in solving one of the equations for the
   project that were posted on the blackboards. However, they did not "do
   the physics right" and Feynman's solution was not used in the project.

   Feynman's other work at Los Alamos included calculating neutron
   equations for the Los Alamos "Water Boiler", a small nuclear reactor at
   the desert lab, to measure how close a particular assembly of fissile
   material was to becoming critical. On completing this work he was
   transferred to the Oak Ridge facility, where he aided engineers in
   calculating safety procedures for material storage, so that inadvertent
   criticality accidents, (e.g., by storing individually subcritical
   amounts of fissile material in proximity on opposite sides of a wall)
   could be avoided. He also did crucial theoretical work and calculations
   on the proposed uranium-hydride bomb, which was later to prove to be
   unfeasible.

   Feynman was sought out by the famous physicist Niels Bohr for
   one-on-one discussions. He later discovered the reason: most 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 just as much respect
   for Bohr's reputation as anyone else, but that once anyone got him
   talking about physics, he could not help but forget about anything
   else.
   Feynman's ID badge photo from Los Alamos.
   Feynman's ID badge photo from Los Alamos.

   Due to the top secret nature of the work, Los Alamos was isolated; in
   his own words, "There wasn't anything to do there". Bored, Feynman
   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 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 in which a colleague kept a
   comprehensive set of atomic bomb research notes all had the same
   combination. He left a series of notes as a prank, which initially
   spooked his colleague into thinking a spy or saboteur had gained access
   to atomic bomb secrets (coincidentally, Feynman once borrowed the car
   of physicist Klaus Fuchs who was later discovered to be a spy for the
   Soviets). On another occasion, he observed that a captain in his
   building at Los Alamos had a massive safe, better than anything the
   bomb scientists had, installed with much ado in his office. Some time
   after the captain left Los Alamos, Feynman discovered that the captain
   had firstly never bothered to change the combination from the generic
   factory setting, so that even an amateur safecracker could open it, and
   secondly there was nothing important being kept in the safe anyway,
   whereas all the secrets of the bomb scientists were mostly kept in
   relatively insecure locked cabinets.

   On occasion, Feynman would find an isolated section of the mesa to drum
   Indian-style; "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
   laboratory head J. Robert Oppenheimer, who unsuccessfully tried to
   court him away from his other commitments to work at the University of
   California, Berkeley after the war.

Early career

   After the project concluded, Feynman began work as a professor at
   Cornell University, where Hans Bethe (who proved that the sun's source
   of energy was nuclear fusion) worked. However, he felt uninspired
   there; despairing that he had burned out, he turned to less useful, but
   fun problems, such as analyzing the physics of a twirling, nutating
   dish, as it is being balanced by a juggler. (As it turned out, this
   work served him well in future research.) He was therefore surprised to
   be offered professorships from competing universities, eventually
   choosing to work at the California Institute of Technology at Pasadena,
   California, despite being offered a position near Princeton, at the
   Institute for Advanced Study (which included such distinguished faculty
   members as Albert Einstein).

   Feynman rejected the Institute on the grounds that there were no
   teaching duties. Feynman found his students to be a source of
   inspiration and, during uncreative times, comfort. He felt that if he
   could not be creative, at least he could teach. Another major factor in
   his decision was a desire to live in a mild climate, a goal he chose
   while having to put snow chains on his car's wheels in the middle of a
   snowstorm in Ithaca, New York.

   Feynman is sometimes called the "Great Explainer"; he took great care
   when explaining topics to his students, making it a moral point not to
   make a topic arcane, but instead accessible to others. His 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 of the connection between
   spin and statistics (that groups of particles with spin 1/2 "repel",
   whereas groups with integer spin "clump"), a question he pondered in
   his own lectures and to which he demonstrated the solution in the 1986
   Dirac memorial lecture. He opposed rote learning and other teaching
   methods that emphasized form over function, everywhere 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 to
   even approach him when unprepared, and he did not forget the fools or
   pretenders.

   During one sabbatical year, he returned to Newton's Principia to study
   it anew; what he learned from Newton, he passed along to his students,
   such as Newton's attempted explanation of diffraction.

The Caltech years

   Feynman did much of his best work while at Caltech, including research
   in:
     * Quantum electrodynamics. The theory for which Feynman won his Nobel
       Prize is known for its extremely accurate predictions. He helped
       develop a functional integral formulation of quantum mechanics, in
       which every possible path from one state to the next is considered,
       the final path being a sum over the possibilities.

     * Physics of the superfluidity of supercooled liquid helium, where
       helium seems to display a lack of viscosity when flowing. Applying
       the Schrödinger equation to the question showed that the superfluid
       was displaying quantum mechanical behaviour observable on a
       macroscopic scale. This helped enormously with the problem of
       superconductivity.

     * A model of weak decay, which showed that the current coupling in
       the process is a combination of vector and axial (an example of
       weak decay is the decay of a neutron into an electron, a proton,
       and an anti- neutrino). Although E.C. George Sudharsan and Robert
       Marshak developed the theory nearly simultaneously, Feynman's
       collaboration with Murray Gell-Mann was seen as seminal; the theory
       was of massive importance, and the weak interaction was neatly
       described.

   He also developed Feynman diagrams, a bookkeeping device which helps in
   conceptualizing and calculating interactions between particles in
   spacetime, notably the interactions between electrons and their
   antimatter counterparts, positrons. This device allowed him, and later
   others, to work with concepts that would have otherwise been less
   approachable, such as time reversibility and other fundamental
   processes. Feynman famously painted Feynman diagrams on the exterior of
   his van.

   Feynman diagrams are now fundamental for string theory and M-theory,
   and have even been extended topologically. Feynman's mental picture for
   these diagrams started with the hard sphere approximation, and the
   interactions could be thought of as collisions at first. It was not
   until decades later that physicists thought of analyzing the nodes of
   the Feynman diagrams more closely. The world-lines of the diagrams have
   developed to become tubes to allow better modelling of more complicated
   objects such as strings and M-branes.

   From his diagrams of a small number of particles interacting in
   spacetime, Feynman could then model all of physics in terms of those
   particles' spins and the range of coupling of the fundamental forces.
   Feynman attempted an explanation of the strong interactions governing
   nucleons scattering called the parton model. The parton model emerged
   as a rival to the quark model developed by his Caltech colleague Murray
   Gell-Mann. The relationship between the two models was murky; Gell-Mann
   referred to Feynman's partons derisively as "put-ons". Feynman did not
   dispute the quark model; for example, when the fifth quark was
   discovered, Feynman immediately pointed out to his students that the
   discovery implied the existence of a sixth quark, which was duly
   discovered in the decade after his death.

   After the success of quantum electrodynamics, Feynman turned to quantum
   gravity. By analogy with the photon, which has spin 1, he investigated
   the consequences of a free massless spin 2 field, and was able to
   derive the Einstein field equation of general relativity, but little
   more. However, a calculational technique that Feynman developed for
   gravity in 1962 — "ghosts" — later proved invaluable. In 1967, Fadeev
   and Popov quantized the particle behaviour of the spin 1 theories of
   Yang-Mills -Shaw -Pauli, that are now seen to describe the weak and
   strong interactions, using Feynman's path integral technique. At this
   time he exhausted himself by working on multiple major projects at the
   same time, including his Lectures in Physics.

   While at Caltech, Feynman was asked to "spruce up" the teaching of
   undergraduates. After three years devoted to the task, he produced a
   series of lectures that would eventually become the Feynman Lectures on
   Physics, one reason that Feynman is still regarded as one of the
   greatest teachers of physics. He wanted a picture of a drumhead
   sprinkled with powder to show the modes of vibration at the beginning
   of the book; the publishers misunderstood him, and the books instead
   carried a picture of him playing drums. Feynman later won the Oersted
   Medal for teaching, of which he seemed especially proud. His students
   competed keenly for his attention; he was once woken when a student
   solved a problem and dropped it in his mailbox; glimpsing the student
   sneaking across his lawn, he could not go back to sleep, and he read
   the student's solution. The next morning his breakfast was interrupted
   by another triumphant student, but Feynman informed him that he was too
   late.

   Partly as a way to bring publicity to progress in physics, Feynman
   offered $1000 prizes for two of his challenges in nanotechnology. He
   was also one of the first scientists to conceive the possibility of
   quantum computers. Many of his lectures and other miscellaneous talks
   were turned into books, including The Character of Physical Law and
   QED: The Strange Theory of Light and Matter. He gave lectures which his
   students annotated into books, such as Statistical Mechanics and
   Lectures on Gravity. The Feynman Lectures on Physics required two
   physicists, Robert B. Leighton and Matthew Sands as full-time editors
   for several years. Even though they were not adopted by the
   universities as textbooks, the books continue to be bestsellers because
   they provide a deep understanding of physics. As of 2005, The Feynman
   Lectures on Physics have sold over 1.5 million copies in English, an
   estimated 1 million copies in Russian, and an estimated half million
   copies in other languages.

   In 1974 Feynman delivered the Caltech commencement address on the topic
   of cargo cult science, which has the semblance of science but is only
   pseudoscience due to a lack of integrity on the part of the scientist.
   He instructed the graduating class that "The first principle is that
   you must not fool yourself—and you are the easiest person to fool. So
   you have to be very careful about that. After you've not fooled
   yourself, it's easy not to fool other scientists. You just have to be
   honest in a conventional way after that."

   In the late 1970's, according to "Richard Feynman and the Connection
   Machine", Feynman played a critical role in developing the first
   parallel-processing computer and finding innovative uses for it in
   numerical computing and building neural networks, as well as physical
   simulation with cellular automata (such as turbulent fluid flow),
   working with Stephen Wolfram at Caltech.

   Shortly before his death, Feynman criticized string theory in an
   interview: "I don't like that they're not calculating anything," he
   said. "I don't like that they don't check their ideas. I don't like
   that for anything that disagrees with an experiment, they cook up an
   explanation - a fix-up to say, 'Well, it still might be true.'" These
   words have since been much-quoted by opponents of the string-theoretic
   direction for particle physics.

Personal life

   He was married a second time in June 1952, to Mary Louise Bell of
   Neodesha, Kansas; this marriage was brief and unsuccessful. He later
   married Gweneth Howarth from the United Kingdom, who shared his
   enthusiasm for life and spirited adventure. Besides their home in
   Altadena, California, they had a beach house in Baja California. They
   remained married until Feynman's death, had a son, Carl, in 1962, and
   adopted a daughter, Michelle, in 1968.

   Feynman had a great deal of success teaching Carl using 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
   did not apply for 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. One coworker characterized Feynman as akin to
   Don Quixote at his desk, rather than at a computer workstation, ready
   to do battle with the windmills.

   According to his colleague, Professor Steven Frautschi, Feynman was the
   only person in the Altadena region to buy flood insurance after the
   massive 1978 fire, predicting correctly that the fire's destruction
   would lead to land erosion, causing mudslides and flooding. The flood
   occurred in 1979 after winter rains and destroyed multiple houses in
   the neighbourhood.

   Feynman traveled a great deal, notably to Brazil, and near the end of
   his life schemed to visit the Russian land of Tuva, a dream that, due
   to Cold War bureaucratic problems, never became reality. During this
   period he discovered that he had a form of cancer, but, thanks to
   surgery, he managed to hold it off. Out of his enthusiastic interest in
   reaching Tuva came the phrase " Tuva or Bust" (also the title of a book
   about his efforts to get there), which was tossed about frequently
   amongst his circle of friends in hope that they, one day, could see it
   firsthand. The documentary movie Genghis Blues mentions some of his
   attempts to communicate with Tuva and chronicles the journey when some
   of his friends did make it there. His attempts to write and send a
   letter using an English-Russian and Russian-Tuvan dictionary
   demonstrate his usual zest for life.

   Feynman did not work only on physics, and had a large circle of friends
   from all walks of life, including the arts. He took up painting at one
   time and enjoyed some success under the pseudonym "Ofey", culminating
   in an exhibition dedicated to his work. He learned to play drums
   (frigideira) in a samba style in Brazil by dint of persistence and
   practice, and participated in a samba school. Feynman even translated
   Mayan hieroglyphics. Such actions earned him a reputation of
   eccentricity.

   According to Genius, the James Gleick biography, Richard Feynman
   experimented with LSD during his professorship at Caltech. Somewhat
   embarrassed by his actions, Feynman sidestepped the issue when
   dictating his anecdotes; consequently, the "Altered States" chapter in
   Surely You're Joking, Mr. Feynman! describes only marijuana and
   ketamine experiences at John Lilly's famed sensory deprivation tanks,
   as a way of studying consciousness. Feynman gave up alcohol when he
   began to show early signs of alcoholism, as he did not want to do
   anything that could damage his brain.

   Feynman also had very liberal views on sexuality and was not ashamed of
   admitting it. In Surely You're Joking, Mr. Feynman!, he gives advice on
   the best way to pick up a girl in a hostess bar. At Caltech, he used a
   nude/topless bar as an office away from his usual office, making
   sketches or writing physics equations on paper placemats. When the
   county officials tried to close the locale, all visitors except Feynman
   refused to testify in favour of the bar, fearing that their families
   would learn about their visits. Only Feynman accepted, and in court, he
   affirmed that the bar was a public need, stating that craftsmen,
   technicians, engineers, common workers "and a physics professor"
   frequented the establishment. The bar was allowed to remain open.
   Feynman served on the presidential commission investigating the 1986
   Challenger disaster. He concluded that NASA management's space shuttle
   reliability estimate to be fantastically unrealistic. He warned in his
   appendix to the commission's report: "For a successful technology,
   reality must take precedence over public relations, for nature cannot
   be fooled." Enlarge
   Feynman served on the presidential commission investigating the 1986
   Challenger disaster. He concluded that NASA management's space shuttle
   reliability estimate to be fantastically unrealistic. He warned in his
   appendix to the commission's report: "For a successful technology,
   reality must take precedence over public relations, for nature cannot
   be fooled."

Later years

   Feynman was requested to serve on the Presidential Rogers Commission
   which investigated the Challenger disaster of 1986. Drawing upon clues
   from a source with inside information, Feynman famously showed on
   television the crucial role in the disaster played by the booster's
   O-ring flexible gas seals with a simple demonstration using a glass of
   ice water, a clamp, and a sample of O-ring material. His opinion of the
   cause of the accident differed from the official findings and was
   considerably more critical of the role of management in sidelining the
   concerns of engineers. After much petitioning, Feynman's minority
   report was included as an appendix to the official document. Feynman's
   book, What Do You Care What Other People Think?, includes a copy of
   that appendix and stories about his work on the commission. In the
   appendix, Feynman concluded that NASA management greatly over-estimated
   space shuttle reliability, offering his own estimate of 98% reliability
   (one failure per 50 flights), in stark contrast to the NASA management
   estimate of one failure in 100,000 flights. Feynman's estimate appears
   justified, with two failures in 116 flights as of 2006.

   The cancer returned in 1987, with Feynman entering the hospital a year
   later. Complications with surgery worsened his condition, whereupon he
   decided to not accept any more treatment and die with dignity. He died
   in Los Angeles, California on February 15, 1988. According to his
   sister, Joan, his last words were "I'd hate to die twice, it's so
   boring." He and his wife Gweneth, who died in 1989, are buried in
   Mountain View Cemetery, Altadena, California.

Commemorations

   On May 4, 2005 the United States Postal Service issued the American
   Scientists commemorative set of four 37-cent self-adhesive stamps in
   several configurations. The scientists depicted were Richard Feynman,
   John von Neumann, Barbara McClintock and Josiah Willard Gibbs.
   Feynman's stamp, sepia-toned, features a photograph of a 30-something
   Feynman and eight small Feynman diagrams.

   A shuttlecraft named after Feynman appeared in two episodes of the
   science fiction television show Star Trek: The Next Generation ("The
   Nth Degree," 1991; "Chain of Command, Part 1," 1992). An error in the
   art department, however, caused the shuttle name to be misspelled,
   "FEYMAN."

   Feynman appears in the fiction book The Diamond Age as one of the
   heroes of the world where nanotechnology is ubiquitous. His
   relationship with his first wife Arline, who died during the Manhattan
   Project, is portrayed in the 1996 movie Infinity.

   Apple's "Think Different" ad campaign featured photo portraits of
   Feynman that appeared in magazines and on posters and billboards.
   (Curiously, the ad shows Feynman wearing a Thinking Machines T-shirt.)

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