Richard Feynman

Feynman was born on May 11, 1918, in the borough of Queens in New York City. His father, Melville Feynman, was a businessman, and his mother, Lucille Phillips, had trained as a primary school teacher. His father had a keen interest in science and did all he could to steer him toward science during his childhood. When he was ten, the family settled in Far Rockaway; he taught himself a great deal of science from the Encyclopaedia BritannicaEncyclopædia BritannicaEncyclopædia Britannica is a general English-language encyclopedia first published in Edinburgh, Scotland, in 1768; the name also refers to its publisher, Chicago-based Encyclopædia Britannica, Inc. (which presents itself as The Britannica Group). The print edition ended in 2012, and the company’s main businesses since then have been the online encyclopedia Britannica.com, digital education products for schools and libraries, and Merriam-Webster dictionaries.Open the full entry, learned elementary mathematics on his own before meeting it at school, and set up a laboratory in his room, where he wired circuits, built a burglar alarm, and repaired radios.⁠[1][2][2][2][2][2][2][2]

He went to high school in Far Rockaway, where his interests were almost entirely mathematics and science, and in his final year he won the New York University Math Championship. When he applied to universities, his grades in mathematics and science were outstanding but much weaker in other subjects, and American universities of the time also had quotas on Jewish students; Columbia UniversityColumbia UniversityColumbia University, formally Columbia University in the City of New York, is a private research university in New York City and a member of the Ivy League. Founded in 1754 by royal charter from King George II as King's College, it is the oldest institution of higher education in New York State and the fifth oldest in the United States. It was renamed Columbia College in 1784 and adopted the university name and moved to Manhattan's Morningside Heights in 1896. It has 17 schools and four affiliated colleges, with 35,978 students enrolled in fall 2025. Legal scholar Jennifer L. Mnookin became president on July 1, 2026.Open the full entry turned him down, and the Massachusetts Institute of Technology accepted him.⁠[1][2][2][2][2][2][2]

In 1935, Feynman entered the Massachusetts Institute of Technology. He began in mathematics, switched to electrical engineering because he found the courses too abstract and lacking in applications, and soon moved again into physics. In his second year he took Introduction to Theoretical Physics, a class intended for graduate students; since the school then had no course on quantum mechanics, in the spring of 1936 he and fellow undergraduate T. A. Welton began studying the available texts on their own. In 1939, he received his BS degree in physics and was named a Putnam Fellow the same year.⁠[2][2][2][2][2][1][3]

John Slater, head of physics at MIT, advised him to go elsewhere for his doctorate and recommended PrincetonPrinceton UniversityPrinceton University is a private university and Ivy League member in Princeton, New Jersey. Chartered on October 22, 1746 as the College of New Jersey, it moved to Princeton in 1756 and adopted its present name in 1896. Undergraduate education leads to A.B. and B.S.E. degrees and emphasizes small-group discussion, independent research and residential college life. Graduate education spans the humanities, social sciences, natural sciences and engineering. As of October 2026, Christopher L. Eisgruber was president. Its 2026–27 operating budget was $3.407 billion, including $342 million for undergraduate aid.Open the full entry; Princeton’s physics department had reservations about admitting Jewish students at the time and accepted him only after further letters from Slater. From 1940 to 1942, Feynman studied at Princeton University as a Proctor Fellow, also serving as a research assistant from 1940 to 1941, and began his investigation of quantum electrodynamics under the supervision of John A. Wheeler.⁠[2][2][2][1][4]

While working for Wheeler, he developed an idea about the interaction between charges and discussed it with Wheeler, which became the starting point of his later space-time view of quantum electrodynamics. The audience at his first seminar at Princeton included Einstein, Pauli, and von Neumann. His doctoral thesis dealt with the principle of least action in quantum mechanics; because Wheeler had gone to Chicago to work on the nuclear reactor, Eugene Wigner advised him to write up his thesis, and after examination by both men he received his doctorate in June 1942. He later said in his Nobel Lecture that he had not truly resolved the difficulty in his thesis, but had published the thesis and received his PhD during one of the short periods when he imagined he had laid it to rest.⁠[5][5][2][1][2][5]

While a doctoral student at Princeton, Feynman was recruited for the atomic bomb project. He at first refused because his thesis was in its final stages, but changed his mind on considering that Nazi Germany might build the bomb first. He was recruited by Robert Wilson and joined as a junior physicist at only 24. He first worked at Princeton on the theory of separating uranium-235 from uranium-238, and then moved to the newly built Los Alamos laboratory.⁠[1][2][2][3][2][2]

At Los Alamos he was assigned to the theoretical division led by Hans Bethe and soon became a group leader, heading a team that carried out complicated calculations on very primitive computing machines and helping devise a formula to predict the energy yield of an atomic bomb. He was also briefly transferred to Oak Ridge, where he helped engineers calculate safety procedures for storing nuclear material so that inadvertent criticality accidents could be avoided. At Los Alamos he was known for picking locks and challenging the security rules, which did not amuse his superiors.⁠[3][1][6][3][3][7]

In 1945, Feynman was present at the Trinity nuclear test and watched the explosion through his truck windshield.⁠[3]

He later said in an interview for the television series Nova that the moral question of working on the bomb was initially set aside because Germany was also building one, but that after Germany’s defeat he did not reconsider: “I simply didn’t think.” After the war he came to believe that everything was doomed to be destroyed, felt it senseless when he saw people building a bridge, and fell into a depressed state. He regretted not reexamining his work after Germany surrendered, though he still felt the threat of a nuclear-armed Nazi Germany justified his initial participation.⁠[7][7][7][7][3]

Feynman became good friends with Hans Bethe at Los Alamos, and at the end of the war Bethe secured him a position as associate professor of physics at Cornell UniversityCornell UniversityCornell University is a private research university in Ithaca, New York, and a member of the Ivy League. It is New York State's federal land-grant university, a distinction unique within the Ivy League. Ezra Cornell and Andrew Dickson White founded the university in 1865, and it opened in 1868. In addition to its Ithaca campus, Cornell operates Weill Cornell Medicine and Cornell Tech in New York City and a medical college in Qatar. It enrolled 26,793 students in fall 2024. Its president is Michael I. Kotlikoff.Open the full entry. He turned down an offer from the Institute for Advanced Study and in the autumn of 1945 followed Bethe to Cornell, where he taught theoretical physics until 1950.⁠[1][3][2]

When he first arrived at Cornell, Feynman devoted himself to teaching and set research aside, later returning to the quantum electrodynamics he had worked on before the war. Laurie M. BrownBrown UniversityBrown University is a private nonprofit research university in Providence, Rhode Island, and a member of the Ivy League. Chartered by Rhode Island's colonial legislature in 1764, it is known for its undergraduate Open Curriculum, which has no common required core. Christina H. Paxson, president since July 2012, announced on August 3, 2026, that the 2026–27 academic year would be her last in office. As of October 1, 2026, the search for Brown's 20th president remained underway.Open the full entry, his graduate student at the time, recalled that Feynman worked with great intensity and often brought his newest ideas into his courses before writing them up for publication, leaving students used to conventional field theory struggling to adapt.⁠[2][2][8][8][8]

In 1947, Lamb and Retherford discovered that energy levels of hydrogen that should coincide theoretically were in fact slightly shifted (the Lamb shift), while the old quantum electrodynamics gave infinite results when calculating the electron’s mass and charge. That year Feynman took part in the Shelter Island Conference, where he introduced his theory of quantum electrodynamics to leading American physicists. Bethe’s insistence on accounting for the experimental value of the Lamb shift from theory pushed Feynman to take up the problem, and Bethe explained to him at the blackboard how to calculate the self-energy of an electron.⁠[9][9][1][1][5][5]

At Cornell, Feynman developed path-integral and diagrammatic methods for calculating how charged quantum particles behave in an electromagnetic field. In April 1948 he published “Space-Time Approach to Non-Relativistic Quantum Mechanics” in Reviews of Modern Physics. That year he introduced the graphic representations later known as Feynman diagrams, which depict the various interactions between particles and greatly simplify the calculation of interaction probabilities.⁠[10][11][12]

The September 15, 1949, issue of Physical Review (volume 76, issue 6) carried both his “The Theory of Positrons” and “Space-Time Approach to Quantum Electrodynamics.” The Nobel Committee later observed that he used more radical methods than his contemporaries to solve the problems of quantum electrodynamics; in his description the electromagnetic field no longer appeared explicitly, which proved especially useful in elementary particle physics, where other interactions must also be considered.⁠[13][14][9][9]

In 1950, Feynman moved to the California Institute of Technology as professor of theoretical physics, first as a visiting professor and then with a regular appointment, and he taught there for the rest of his life. Because he had planned a sabbatical before receiving the offer, he spent the first ten months of the new appointment in Brazil. Later, to lecture in Brazil, he spent six weeks learning Portuguese and delivered a series of lectures on quantum theory in Portuguese.⁠[15][4][8][2][15]

The January 1, 1958, issue of Physical Review (volume 109, issue 1) published “Theory of the Fermi Interaction,” coauthored by Feynman and Murray Gell-Mann, which put forward a model of weak decay.⁠[16][3]

In 1959, Feynman became Richard Chace Tolman Professor of Theoretical Physics at Caltech, a chair he held until his death.⁠[15][8][1]

On December 29, 1959, Feynman gave the talk “There’s Plenty of Room at the Bottom” at the annual meeting of the American Physical Society at Caltech; the text appeared in the February 1960 issue of the Caltech magazine Engineering and Science (volume 23, number 5). In the talk he discussed manipulating and controlling things on a small scale, imagined writing all 24 volumes of the Encyclopaedia Britannica on the head of a pin, and argued that the principles of physics do not rule out maneuvering matter atom by atom.⁠[17][18][18][18][18][18][18][18]

At the end of the talk he offered two prizes of $1,000 each: one to the first person to shrink the information on a page of a book to 1/25,000 of its linear size in a form readable by an electron microscope, and one to the first person to build an operating rotating electric motor, controllable from the outside, only 1/64 inch on a side not counting the lead-in wires. Less than a year later, Caltech alumnus Bill McLellan built such a motor, and Feynman paid out the prize.⁠[18][18][18][18][18][18][17]

Caltech physicist Matthew Sands pushed to reform the introductory course, which then contained almost no modern physics, and when he and Robert Leighton could not agree on a syllabus he proposed asking Feynman to give the lectures himself. Feynman was not immediately enthusiastic, but after asking Sands whether a great physicist had ever presented a course to freshmen and hearing that none had, he agreed: “I’ll do it.” Department head Robert Bacher, worried about the graduate program, was at first opposed but eventually agreed.⁠[19][19][19][19][19][19][19]

From September 1961, Feynman lectured on introductory physics to Caltech’s first- and second-year students for two academic years, giving two one-hour lectures a week. He lectured with a microphone around his neck connected to a tape recorder, the blackboards were photographed periodically, and the transcripts were edited under Robert Leighton’s direction so that students had printed notes to study. Sands recalled that Feynman brought only one or two small slips of paper as notes and rarely looked at them, and that each lecture was carefully staged through introduction, development, climax, and denouement, with impressive timing.⁠[19][19][19][19][19][19][19][19]

In the spring of 1963, Leighton and Sands decided to turn the transcripts into a book and chose Addison-Wesley, which promised hardbound books in time for the class of September 1963 and, because the authors were not requesting royalties, a relatively low price. After some dispute, the title was settled as The Feynman Lectures on Physics, by Feynman, Leighton, and Sands. Around June 1963, Feynman dictated the first draft of the preface into a Dictaphone, writing in it, “I don’t think I did very well by the students.”⁠[19][19][19][19][19][19][19]

The second-year lectures were split into two volumes, one mainly on electromagnetism and the other on quantum mechanics, and Feynman gave additional lectures on quantum physics for the third volume. Sands completed the final editing of the second volume in March 1964 and of the third volume that December. Caltech holds the copyright to the lectures.⁠[19][19][19][19][1]

At 3:45 a.m. on October 21, 1965, a call from the American Broadcasting CompanyABCABC (American Broadcasting Company) is an American commercial broadcast television network. It grew out of NBC’s Blue radio network, took its name after becoming independent in 1943, developed into a national television network after merging with United Paramount Theatres in 1953, was acquired by Capital Cities in 1985, and has been owned by The Walt Disney Company since 1996. With CBS and NBC it is one of the three traditional U.S. broadcast networks, and it is one of the five networks that rotate in the White House television pool.Open the full entry woke Feynman to tell him he had won the Nobel Prize in Physics; he replied that he could have found out later that morning. A telegram from the Royal Swedish Academy of Sciences then confirmed that he, Sin-Itiro Tomonaga, and Julian Schwinger had jointly been awarded the 1965 Nobel Prize in Physics “for their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics of elementary particles,” each receiving one-third of the prize. The three had done their work independently between 1947 and 1949, and the prize totaled $55,000.⁠[15][15][15][20][12][15]

That morning he met the press at the Athenaeum on the Caltech campus. Asked whether his work could be explained in layman’s terms, he said, “There certainly must be. But I don’t know what it is.” He later said that he had at first considered refusing the prize, but realized that refusing would cause a bigger stir than accepting.⁠[15][15][7]

At the award ceremony on December 10, 1965, Ivar Waller of the Nobel Committee for Physics gave the presentation speech, noting that one important result of the laureates’ work was the explanation of the Lamb shift and calling the new quantum electrodynamics one of the most accurate theories in physics. Tomonaga was prevented by an accident from attending, and his prize was to be presented through the Swedish ambassador in Tokyo.⁠[9][9][9][9]

That evening Feynman spoke at the Nobel Banquet, saying that the flood of congratulations from friends, students, teachers, and even strangers had made him feel a depth of affection he had never felt so poignantly before. On December 11 he delivered his Nobel Lecture, “The Development of the Space-Time View of Quantum Electrodynamics,” which instead of presenting the finished theory traced, through personal experience, the path of ideas that led him to it, including its wrong turns; the lecture was published in Physics Today in August 1966.⁠[21][21][21][5][5][10]

The December 15, 1969, issue of Physical Review Letters (volume 23, issue 24) published Feynman’s paper “Very High-Energy Collisions of Hadrons.” His theory of “partons” advanced the understanding of particle physics and led toward the current theory of quarks.⁠[22][2]

In June 1982, Feynman published “Simulating physics with computers” in the International Journal of Theoretical Physics (volume 21, issues 6–7). The National Science and Technology Medals Foundation lists him as one of the first scientists to conceive of the possibility of quantum computers.⁠[23][6]

In 1985, Feynman published the memoir Surely You’re Joking, Mr. Feynman!, a collection of youthful pranks and adult triumphs that became a surprise best seller, though he said he never understood its success. QED: The Strange Theory of Light and Matter, published the same year, originated in his Mautner Lectures, which had been preceded by the same material delivered as the Robb Lectures at the University of Auckland in New Zealand.⁠[2][1][7][2][2][1]

After the space shuttle Challenger exploded on January 28, 1986, President Reagan announced on February 3 the formation of a commission to investigate the accident, charged under Executive Order 12546 with establishing its probable cause and recommending corrective action. William P. Rogers chaired the commission, Neil A. Armstrong was vice chairman, and Feynman served as a member as a physicist. He had long avoided committee assignments and accepted this appointment reluctantly, but threw himself into the work.⁠[2][24][24][25][26][7][7]

On February 11, 1986, the commission held a public hearing in Washington. Before the television cameras, Feynman clamped a piece of synthetic rubber O-ring from a model of the shuttle in an ordinary C-clamp, dropped it into a glass of ice water, then took it out and released the clamp. He then told Lawrence Mulloy that when this seal material was squeezed for a while in ice water and released, it did not stretch back, and that at 32 degrees Fahrenheit (0 degrees Celsius) it had no resilience at all for at least several seconds: “I believe that has some significance for our problem.” Chairman Rogers said the point would be considered at length in the session on the weather.⁠[25][7][7][25][25][25]

The demonstration, which Feynman called a “little experiment,” showed plainly that cold weakened the O-ring’s resilience; weeks later, the final report the commission presented to the President reached essentially the same conclusion.⁠[7][7]

On June 6, 1986, the commission presented its report to the President. Feynman’s “Personal Observations on Reliability of Shuttle” was included as Appendix F in volume 2 of the report. In it he wrote that estimates of the probability of shuttle failure ranged from roughly 1 in 100 to 1 in 100,000, the higher figures coming from working engineers and the very low ones from management; that certification criteria in Flight Readiness Reviews tended to grow gradually less strict, with the fact that the same risk had been flown before without failure accepted as grounds for accepting it again; and that seals that had shown erosion and blow-by on earlier flights had therefore been cleared for flight again and again.⁠[27][28][28][28][28]

He concluded that the shuttle actually flew in a relatively unsafe condition, with a chance of failure of the order of a percent, while management claimed a probability a thousand times lower, and that this exaggeration of reliability encouraged ordinary citizens to fly in such a dangerous machine; he recommended proposing only flight schedules with a reasonable chance of being met. He later wrote up his experience of the inquiry as “An Outsider’s Inside View of the Challenger Inquiry,” published in Physics Today in February 1988, and recounted the investigation in his own words in the book What Do You Care What Other People Think?⁠[28][28][28][28][8][2][2]

On the night of February 15, 1988, Feynman died at the University of California at Los Angeles Medical Center in Los Angeles, at the age of 69. He had continued teaching at Caltech until two weeks before his death.⁠[12][7][2][2]

On January 18, 1989, an all-day memorial session for Feynman was held in San Francisco at a joint meeting of the American Association of Physics Teachers, the American Physical Society, and the American Association for the Advancement of Science, with speakers including John Archibald Wheeler, Julian Schwinger, Freeman J. Dyson, and Murray Gell-Mann. Physics Today then published a special memorial issue in February 1989, quoting Hans Bethe: there are two kinds of geniuses, the ordinary kind whose achievements make others feel they could do the same if they worked hard enough, and the kind who performs magic, “and that’s Feynman.”⁠[8][8][8][8][8][8]

Feynman’s working papers entered the Caltech Archives in two groups: the first was donated by Feynman himself in 1968, and the second, just under three-fourths of the whole collection, was given by his widow, Gweneth, early in 1989.⁠[1][1]

Besides quantum electrodynamics, Feynman worked at Caltech on the physics of superfluidity in liquid helium, particle physics, and later quantum chromodynamics, and also worked on quantum gravity; his working notes range from quantum electrodynamics to biology and computers.⁠[3][1][3][1]

His colleague Robert Leighton said Feynman made things seem so simple in the classroom that students thought they understood, only to wonder at home, “How did he do that?” In 1964 he also served on the California State Curriculum Commission, helping select textbooks for elementary-grade arithmetic courses.⁠[7][7][15]

Laurie M. Brown observed that Feynman liked to project the image of a rough-mannered showman who triumphs through cleverness, common sense, and humor; delightful as it was, that image left out his scientific genius, his deep love of nature, his passion for teaching, and his extraordinary standards of personal integrity.⁠[8][8][8]

Feynman enjoyed camping with his family, playing the bongo drums, and drawing, and once traded physics lessons for drawing lessons with an artist friend; his fondness for codes and safecracking, his theatrical appearances, and his artwork are well documented in his memoirs and in his papers at Caltech.⁠[15][1][1]

Feynman’s principal honors include the Albert Einstein Award (1954); the Ernest Orlando Lawrence Memorial Award of the Atomic Energy Commission (1962); election as a foreign member of the Royal Society (1965); the Nobel Prize in Physics (1965); the Oersted Medal (1972); and the Niels Bohr International Gold Medal (1973). In 1979 he received the National Medal of Science (Physical Sciences), awarded by President Jimmy CarterJimmy CarterJimmy Carter (1924–2024) was an American politician and Democrat who served as the 39th president of the United States from 1977 to 1981. His administration brokered the Camp David Accords between Egypt and Israel, signed the Panama Canal treaties and established relations with the People’s Republic of China, but he lost his reelection bid amid the energy crisis, inflation and the Iran hostage crisis; after leaving office he founded The Carter Center to work on mediation, election observation and disease control, and received the Nobel Peace Prize in 2002.Open the full entry, in recognition of his essential contributions to the quantum theory of radiation and his illumination of the behavior of the constituents of the atom, the atomic nucleus, and subnuclear particles. He was also a member of the American Physical Society, the American Association for the Advancement of Science, and the National Academy of Sciences.⁠[15][4][26][6][6][4]

“For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.” — the closing words of Appendix F to the 1986 Challenger accident report.⁠[28]

“What I want to talk about is the problem of manipulating and controlling things on a small scale.” — from the 1959 talk “There’s Plenty of Room at the Bottom.”⁠[18][18]

“The work I have done has, already, been adequately rewarded and recognized.” — the opening of his 1965 Nobel Banquet speech.⁠[21]

“We have a habit in writing articles published in scientific journals to make the work as finished as possible, to cover all the tracks, to not worry about the blind alleys or to describe how you had the wrong idea first” — the opening of his 1965 Nobel Lecture.⁠[5]