He helped in the development of the atomic bomb and was later a member of the panel which investigated the Space Shuttle Challenger disaster. For his work on quantum electrodynamics, Feynman was one of the recipients of the Nobel Prize in Physics for 1965, along with Julian Schwinger and Shin-Ichiro Tomonaga. Feynman wrote only 37 research papers in his career (a remarkably small number for such a prolific researcher), but many consider the two discoveries he made at Caltech, superfluidity and the prediction of quarks, also worthy of the Nobel Prize. Apart from pure physics, Dr. Feynman is also credited with the revolutionary concept and early exploration of quantum computing, and first publicly envisioning nanotechnology, i.e. the ability to mass produce atomic-scale machines.

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 his transcribed lectures, The Feynman Lectures on Physics, a 3-volume set which has become a classic undergraduate text. Known for his insatiable curiosity, gentle wit, brilliant mind and playful temperament, he is also famous for his many adventures, detailed in the books Surely You're Joking, Mr. Feynman!, What Do You Care What Other People Think? and Tuva or Bust!. As well as being an inspiring lecturer, bongo player, notorious practical joker, and decipherer of Mayan hieroglyphics, Richard Feynman was, in many respects, an eccentric and a free spirit. He was an entrepreneur in the sense that, like Leonardo da Vinci before him, he pursued many independent paths, breaking new ground as he went.

Feynman was born in Far Rockaway, Queens, New York; his parents were Jewish and attended temple every Friday, although they were unritualistic in their practice of Judaism as a religion. The young Feynman was heavily influenced by his father, Melville Feynman, who encouraged him to ask questions in order to challenge orthodox thinking. His mother instilled in him a powerful sense of humor which he kept all his life.

As a child, he delighted in repairing radios and had a talent for engineering. At school he was bright, but his measured IQ was merely above average at 124, which he would scoff at later. By age 15, he had mastered differential and integral calculus. He kept experimenting on and re-creating mathematical topics, such as the half-derivative (a mathematical operator, which when applied twice in succession, resulted in the derivative of a function), utilizing his own notation, before entering college.

Thus, even while 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 a zoological chart). When he spoke, it was with clarity.

Education
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 Einstein at the same age, like the Soviet physicist Lev Landau - but few others. — Genius : The Life and Science of Richard Feynman

In his last year at Far Rockaway High School, Feynman won the New York University Math Championship. Feynman received a bachelor's degree from the Massachusetts Institute of Technology in 1939, and was named Putnam Fellow that same year. While there, Feynman had taken every physics course offered, and had taken 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 portion.

Attendees at Feynman's first seminar that he had given 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.

While researching his Ph.D, Feynman married his first wife, Arline Greenbaum. (Arline's first name is often spelled Arlene, as it is in Surely You're Joking, Mr. Feynman and What Do You Care What Other People Think?, two collections of Feynman anecdotes. However, in his own letters, published in Perfectly Reasonable Deviations From the Beaten Track, Feynman wrote his wife's name as Arline.) Arline had been diagnosed with tuberculosis, a terminal illness at that time, but she and Feynman were careful, and he never contracted the disease.

The 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 developing the atomic bomb. Feynman said he was persuaded to join this effort to help make sure that Nazi Germany did not build them first. On weekends, he visited his wife in a sanatorium in Albuquerque, right up until her death on June 16, 1945. 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, his work on the project was relatively remote from the major action, consisting mostly of administering the computation group of human computers in the Theoretical division, and then, with Nicholas Metropolis, setting up the system for using IBM punch cards for computation. John G. Kemeny, later president of Dartmouth College, worked for Feynman at this time. Feynman actually succeeded in solving one of the equations for the project which 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, in order to measure how close a particular assembly of fissile material was to becoming critical. After 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 close proximity on opposite sides of a wall, could be avoided). He also did crucial theoretical and calculation work on the proposed uranium-hydride bomb, which was later proven to be infeasible.

Feynman was also sought out by the famous physicist Niels Bohr for one-on-one discussions. He later found out why. Most physicists were too much in awe of Bohr to argue with him, but Feynman had no such inhibitions, vigorously pointing out anything he considered to be flawed in his 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 couldn't help but forget about anything else.

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 claims 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 a physicist would use (it was 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 (for his convenience while selecting material for declassification) all had the same combination.

He left a series of mischievous notes as a prank, which initially spooked his colleague into thinking a spy or saboteur had actually gained access to atomic bomb secrets. (Coincidentally, Feynman once borrowed the car of physicist Klaus Fuchs in order to visit his sick wife. Fuchs was later discovered to be a spy.) On another occasion, he noted 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 with the massive safe had (1) never bothered to change the combination from the single generic factory setting, so that even an amateur safecracker could open it, and (2) 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. These anecdotes are related by him in the book Surely You're Joking, Mr. Feynman!

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: Cornell University
After the project, Feynman started working 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, at that time, such distinguished faculty 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 also, 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 just a desire to live in a mild climate, a goal he seized on 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 accessible to others. His principle was that if a topic could not be explained in a freshman lecture, it was not fully understood yet. 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 which he solved 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 who the fools or pretenders were.

On one sabbatical year, he returned to Newton's Principia to study it anew; what he learned from Newton, he also 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:

1. 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.
2. 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 behavior observable on a macroscopic scale. This helped enormously with the problem of superconductivity.
3. 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 the seminal one, 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 now others, to work with concepts which would have been less approachable without it, 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 become tubes to better model the 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. The quark model, however, was a rival to Feynman's parton formulation. Feynman did not dispute the quark model; for example, when the 5th quark was discovered, Feynman immediately pointed out to his students that the discovery implied the existence of a 6th 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. Unfortunately, at this time he became exhausted 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, a series of lectures was produced, eventually becoming the famous Feynman Lectures on Physics, which are a major reason that Feynman is still regarded by most physicists as one of the greatest teachers of physics ever. 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 carry 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; once he was awakened when a student solved a problem and dropped it in his mailbox at home; glimpsing the student sneaking across his lawn, he could not go back to sleep, and he read the student's solution. That morning his breakfast was interrupted by another triumphant student, but Feynman informed this student 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 such as 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", Richard 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.

Personal life
Feynman's first wife Arline Greenbaum died of tuberculosis while he was working on the Manhattan project. He married a second time, to Mary Louise Bell of Neodesha, Kansas in June, 1952; 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 for life, 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 Professor Steven Frautschi, a colleague of Feynman, 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 neighborhood.

Feynman traveled a great deal, notably to Brazil, and near the end of his life schemed to visit the obscure Russian land of Tuva, a dream that, due to Cold War bureaucratic problems, never succeeded. 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 of reaching Tuva came the phrase "Tuva or Bust", which was tossed about frequently amongst his circle of friends in hope that they, one day, could see it first-hand.

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. While at Los Alamos on the Top Secret Manhattan Project, he earned the notoriety of being a master safe-cracker. He learned to play drums (frigideira) in acceptable samba style in Brazil by 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 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 and drew artwork for a massage parlor. He used a nude/topless bar as an office away from the office, making sketches or writing physics equations on paper placemats.

Feynman's later years
Feynman was requested to serve on the presidential Rogers Commission which investigated the Challenger disaster of 1986. Fed 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. The book What Do You Care What Other People Think? includes stories from Feynman's work on the commission. His engineering skill is reflected in his 98% estimate of the Space Shuttle's reliability, which is underscored by the two failures over the 114 flights of the Space Shuttle as of 2006.

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

Commemorations of Feynman
On May 4, 2005 the United States Postal Service issued the American Scientists commemorative postage stamp series, a 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.

Quotations

"Dear Mrs. Chown, Ignore your son's attempts to teach you physics. Physics isn't the most important thing. Love is. Best wishes, Richard Feynman."

"Physics is to math what sex is to masturbation."

"Physics is like sex: sure, it may give some practical results, but that's not why we do it."

"Mathematics is not real, but it feels real. Where is this place?"

"The same equations have the same solutions." (Thus when you have solved a mathematical problem, you can re-use the solution in another physical situation. Feynman was skilled in transforming a problem into one that he could solve.)

"When you are solving a problem, don't worry. Now, after you have solved the problem, then that's the time to worry."

"The wonderful thing about science is that it's alive."

"All fundamental processes are reversible."

"What does it mean, to understand? ... I don't know."

"What I cannot create, I do not understand." (Taken from his chalkboard after his death.)

"Know how to solve every problem that has ever been solved." (Taken from his chalkboard after his death.)

"But I don't have to know an answer. I don't feel frightened by not knowing things, by being lost in the mysterious universe without having any purpose—which is the way it really is, as far as I can tell, possibly. It doesn't frighten me."

"To those who do not know mathematics it is difficult to get across a real feeling as to the beauty, the deepest beauty, of nature ... If you want to learn about nature, to appreciate nature, it is necessary to understand the language that she speaks in."

"I cannot define the real problem, therefore I suspect there's no real problem, but I'm not sure there's no real problem." (about Quantum Mechanics)

"I'd hate to die twice. It's so boring" (last words).

"In those days, in Far Rockaway, there was a youth center for Jewish kids at the temple.... Somebody nominated me for president of the youth center. The elders began getting nervous, because I was an avowed atheist by that time.... I thought nature itself was so interesting that I didn't want it distorted like that [by miracle stories]. And so I gradually came to disbelieve the whole religion."

"No! Not for a second! I immediately began to think how this could have happened. And I realized that the clock was old and was always breaking. That the clock probably stopped some time before and the nurse coming in to the room to record the time of death would have looked at the clock and jotted down the time from that. I never made any supernatural connection, not even for a second. I just wanted to figure out how it happened."

"God was invented to explain mystery. God is always invented to explain those things that you do not understand. Now, when you finally discover how something works, you get some laws which you're taking away from God; you don't need him anymore. But you need him for the other mysteries. So therefore you leave him to create the universe because we haven't figured that out yet; you need him for understanding those things which you don't believe the laws will explain, such as consiousness, or why you only live to a certain length of time -- life and death -- stuff like that. God is always associated with those things that you do not understand. Therefore I don't think that the laws can be considered to be like God because they have been figured out."

"By honest I don't mean that you only tell what's true. But you make clear the entire situation. You make clear all the information that is required for somebody else who is intelligent to make up their mind."

"Once we were driving in the midwest and we pulled into a McDonald's. Someone came up to me and asked me why I have Feynman diagrams all over my van. I replied, "Because I am Feynman!" The young man went, "Ahhhhh!""