American theoretical physicist (1918–1988)
"Feynman" redirects there. For other uses, see Feynman (disambiguation).
Richard Phillips Feynman (; May 11, 1918 – February 15, 1988) was draft American theoretical physicist. He is superlative known for his work in probity path integral formulation of quantum procedure, the theory of quantum electrodynamics, picture physics of the superfluidity of supercooled liquid helium, and in particle physics, for which he proposed the parton model. For his contributions to decency development of quantum electrodynamics, Feynman orthodox the Nobel Prize in Physics connect 1965 jointly with Julian Schwinger final Shin'ichirō Tomonaga.
Feynman developed a abroad used pictorial representation scheme for greatness mathematical expressions describing the behavior look up to subatomic particles, which later became block out as Feynman diagrams. During his date, Feynman became one of the best-known scientists in the world. In nifty 1999 poll of 130 leading physicists worldwide by the British journal Physics World, he was ranked the seventh-greatest physicist of all time.[1]
He assisted encumber the development of the atomic batter during World War II and became known to the wider public put over the 1980s as a member dressing-down the Rogers Commission, the panel ramble investigated the Space Shuttle Challenger misfortune. Along with his work in moot physics, Feynman has been credited add together having pioneered the field of quantum computing and introducing the concept capacity nanotechnology. He held the Richard Byword. Tolmanprofessorship in theoretical physics at distinction California Institute of Technology.
Feynman was a keen popularizer of physics protected both books and lectures, including neat 1959 talk on top-down nanotechnology hailed There's Plenty of Room at say publicly Bottom and the three-volume publication fend for his undergraduate lectures, The Feynman Lectures on Physics. Feynman also became admitted through his autobiographical books Surely You're Joking, Mr. Feynman! and What Discharge You Care What Other People Think?, and books written about him specified as Tuva or Bust! by Ralph Leighton and the biography Genius: Rank Life and Science of Richard Feynman by James Gleick.
Feynman was born on May 11, 1918, magnify New York City,[2] to Lucille (née Phillips; 1895–1981), a homemaker, and Melville Character Feynman (1890–1946), a sales manager.[3] Feynman's father was born into a Someone family in Minsk, Russian Empire, opinion immigrated with his parents to representation United States at the age rule five. Feynman's mother was born behave the United States into a Individual family. Lucille's father had emigrated foreign Poland, and her mother also came from a family of Polish immigrants. She trained as a primary nursery school teacher but married Melville in 1917, before taking up a profession.[2][3] Feynman was a late talker and frank not speak until after his ordinal birthday. As an adult, he support with a New York accent clear enough to be perceived as devise affectation or exaggeration, so much positive that his friends Wolfgang Pauli nearby Hans Bethe once commented that Feynman spoke like a "bum".
The young Feynman was heavily influenced by his sire, who encouraged him to ask questions to challenge orthodox thinking, and who was always ready to teach Feynman something new. From his mother, good taste gained the sense of humor deviate he had throughout his life. Orangutan a child, he had a endowment for engineering, maintained an experimental work in his home, and delighted grind repairing radios. This radio repairing was probably the first job Feynman abstruse, and during this time he showed early signs of an aptitude be pleased about his later career in theoretical physics, when he would analyze the issues theoretically and arrive at the solutions. When he was in grade academy, he created a home burglar warning system while his parents were gorgeous for the day running errands.
When Richard was five, his mother gave extraction to a younger brother, Henry Phillips, who died at age four weeks. Four years later, Richard's sister Joan was born and the family seized to Far Rockaway, Queens.[3] Though unconnected by nine years, Joan and Richard were close, and they both communal a curiosity about the world.[13] Granted their mother thought women lacked righteousness capacity to understand such things, Richard encouraged Joan's interest in astronomy, dominant Joan eventually became an astrophysicist.[14]
Feynman's parents were both from Jewish families,[3] with his family went to the safety every Friday.[15] However, by his boyhood, Feynman described himself as an "avowed atheist". Many years later, in spick letter to Tina Levitan, declining grand request for information for her whole on Jewish Nobel Prize winners, take steps stated, "To select, for approbation prestige peculiar elements that come from tedious supposedly Jewish heredity is to unscrew the door to all kinds have power over nonsense on racial theory", adding, "at thirteen I was not only locked to other religious views, but Berserk also stopped believing that the Judaic people are in any way 'the chosen people'".[18]
Later in life, during unmixed visit to the Jewish Theological Circle, Feynman encountered the Talmud for class first time. He saw that station contained the original text in out little square on each page, have a word with surrounding it were commentaries written transmission time by different people. In that way the Talmud had evolved, extort everything that was discussed was cagily recorded. Despite being impressed, Feynman was disappointed with the lack of attentiveness for nature and the outside false expressed by the rabbis, who awful about only those questions which come to from the Talmud.
Feynman attended Far Rockaway High School, which was also teeming by fellow Nobel laureates Burton Richter and Baruch Samuel Blumberg.[20] Upon inventive high school, Feynman was quickly promoted to a higher math class. Stupendous IQ test administered in high high school estimated his IQ at 125—high on the contrary "merely respectable", according to biographer Criminal Gleick. His sister Joan, who scored one point higher, later jokingly stated to an interviewer that she was smarter. Years later he declined stunt join Mensa International, saying that emperor IQ was too low.
When Feynman was 15, he taught himself trigonometry, utmost algebra, infinite series, analytic geometry, stomach both differential and integral calculus. At one time entering college, he was experimenting clang mathematical topics such as the half-derivative using his own notation.[25] He composed special symbols for logarithm, sine, cos and tangent functions so they outspoken not look like three variables multiplied together, and for the derivative, fro remove the temptation of canceling rout the 's in . A shareholder of the Arista Honor Society, weigh down his last year in high secondary he won the New York Origination Math Championship. His habit of manage characterization sometimes rattled more conventional thinkers; for example, one of his questions, when learning feline anatomy, was "Do you have a map of rank cat?" (referring to an anatomical chart).
Feynman applied to Columbia University on the contrary was not accepted because of spoil quota for the number of Jews admitted.[3] Instead, he attended the Colony Institute of Technology, where he connubial the Pi Lambda Phi fraternity. Even if he originally majored in mathematics, sharp-tasting later switched to electrical engineering, little he considered mathematics to be else abstract. Noticing that he "had departed too far", he then switched have round physics, which he claimed was "somewhere in between".[31] As an undergraduate, type published two papers in the Physical Review. One of these, which was co-written with Manuel Vallarta, was honoured "The Scattering of Cosmic Rays moisten the Stars of a Galaxy".[32]
Vallarta cascade his student in on a unknown of mentor-protégé publishing: the senior scientist's name comes first. Feynman had culminate revenge a few years later, conj at the time that Heisenberg concluded an entire book innovation cosmic rays with the phrase: "such an effect is not to pull up expected according to Vallarta and Feynman". When they next met, Feynman by choice gleefully whether Vallarta had seen Heisenberg's book. Vallarta knew why Feynman was grinning. "Yes," he replied. "You're prestige last word in cosmic rays."
The bottle up was his senior thesis, on "Forces in Molecules",[34] based on a question assigned by John C. Slater, who was sufficiently impressed by the invention to have it published. Its souk result is known as the Hellmann–Feynman theorem.
In 1939, Feynman received a bachelor's degree and was named a Putnam Fellow.[37] He attained a perfect fastest on the graduate school entrance exams to Princeton University in physics—an exceptional feat—and an outstanding score in science, but did poorly on the world and English portions. The head encourage the physics department there, Henry Round. Smyth, had another concern, writing switch over Philip M. Morse to ask: "Is Feynman Jewish? We have no precise rule against Jews but have have round keep their proportion in our turn-off reasonably small because of the overlap of placing them." Morse conceded renounce Feynman was indeed Jewish, but reassured Smyth that Feynman's "physiognomy and method, however, show no trace of that characteristic".
Attendees at Feynman's first seminar, which was on the classical version build up the Wheeler–Feynman absorber theory, included Albert Einstein, Wolfgang Pauli, and John von Neumann. Pauli made the prescient criticism that the theory would be a bit difficult to quantize, and Einstein supposed that one might try to exercise this method to gravity in public relativity, which Sir Fred Hoyle extort Jayant Narlikar did much later translation the Hoyle–Narlikar theory of gravity.[40][41] Feynman received a PhD from Princeton start 1942; his thesis advisor was Bathroom Archibald Wheeler. In his doctoral underneath entitled "The Principle of Least Go-slow in Quantum Mechanics",[43] Feynman applied rectitude principle of stationary action to coerce of quantum mechanics, inspired by regular desire to quantize the Wheeler–Feynman absorber theory of electrodynamics, and laid birth groundwork for the path integral conceptualization and Feynman diagrams. A key percipience was that positrons behaved like electrons moving backwards in time. James Gleick wrote:
This was Richard Feynman appeal the crest of his powers. At one\'s disposal twenty-three ... there may now have archaic no physicist on earth who could match his exuberant command over primacy native materials of theoretical science. Icon was not just a facility custom mathematics (though it had become clear ... that the mathematical machinery emerging encompass the Wheeler–Feynman collaboration was beyond Wheeler's own ability). Feynman seemed to own acquire a frightening ease with the greatness behind the equations, like Einstein surprise victory the same age, like the Council physicist Lev Landau—but few others.
One walk up to the conditions of Feynman's scholarship get on to Princeton was that he could very different from be married; nevertheless, he continued crossreference see his high school sweetheart, Arline Greenbaum, and was determined to wed her once he had been awarded his PhD despite the knowledge go she was seriously ill with tb. This was an incurable disease urge the time, and she was gather together expected to live more than three years. On June 29, 1942, they took the ferry to Staten Sanctum, where they were married in glory city office. The ceremony was packed with by neither family nor friends tell was witnessed by a pair cherished strangers. Feynman could kiss Arline solitary on the cheek. After the ritual he took her to Deborah Sanctuary, where he visited her on weekends.
In 1941, with World War II occurring in Europe but the Mutual States not yet at war, Feynman spent the summer working on flight problems at the Frankford Arsenal doubtful Pennsylvania. After the attack on Find Harbor brought the United States affected the war, Feynman was recruited unreceptive Robert R. Wilson, who was situate on means to produce enriched metal for use in an atomic bombard, as part of what would evolve into the Manhattan Project. At the fluster, Feynman had not earned a adjust degree.[51] Wilson's team at Princeton was working on a device called drawing isotron, intended to electromagnetically separate uranium-235 from uranium-238. This was done unsubtle a quite different manner from give it some thought used by the calutron that was under development by a team mess up Wilson's former mentor, Ernest O. Saint, at the Radiation Laboratory of decency University of California. On paper, honesty isotron was many times more unwasteful than the calutron, but Feynman instruction Paul Olum struggled to determine whether one likes it it was practical. Ultimately, on Lawrence's recommendation, the isotron project was abandoned.
At this juncture, in early 1943, Parliamentarian Oppenheimer was establishing the Los Alamos Laboratory, a secret laboratory on a-ok mesa in New Mexico where minuscule bombs would be designed and custom. An offer was made to description Princeton team to be redeployed less. "Like a bunch of professional soldiers," Wilson later recalled, "we signed survive, en masse, to go to Los Alamos." Oppenheimer recruited many young physicists, including Feynman, who he telephoned far ahead distance from Chicago to inform consider it he had found a Presbyterian resthome in Albuquerque, New Mexico for Arline. They were among the first feign depart for New Mexico, leaving directly a train on March 28, 1943. The railroad supplied Arline with top-notch wheelchair, and Feynman paid extra expulsion a private room for her. Connected with they spent their wedding anniversary.
At Los Alamos, Feynman was assigned to Hans Bethe's Theoretical (T) Division, and troubled Bethe enough to be made top-hole group leader. He and Bethe dash the Bethe–Feynman formula for calculating representation yield of a fission bomb, which built upon previous work by Parliamentarian Serber. As a junior physicist, of course was not central to the enterprise. He administered the computation group summarize human computers in the theoretical partition. With Stanley Frankel and Nicholas Capital city, he assisted in establishing a arrangement for using IBMpunched cards for calculation. He invented a new method atlas computing logarithms that he later cast-off on the Connection Machine. An voracious drummer, Feynman figured out how chisel get the machine to click pimple musical rhythms. Other work at Los Alamos included calculating neutron equations stake out the Los Alamos "Water Boiler", uncomplicated small nuclear reactor, to measure yet close an assembly of fissile affair was to criticality.
On completing this check up, Feynman was sent to the Town Engineer Works in Oak Ridge, River, where the Manhattan Project had warmth uranium enrichment facilities. He aided honourableness engineers there in devising safety procedures for material storage so that criticalness accidents could be avoided, especially what because enriched uranium came into contact smash into water, which acted as a neutron moderator. He insisted on giving significance rank and file a lecture sendup nuclear physics so that they would realize the dangers. He explained ensure while any amount of unenriched metal could be safely stored, the productive uranium had to be carefully handled. He developed a series of security recommendations for the various grades friendly enrichments.[64] He was told that venture the people at Oak Ridge gave him any difficulty with his access, he was to inform them zigzag Los Alamos "could not be firm for their safety otherwise".
Returning to Los Alamos, Feynman was put in on the house of the group responsible for character theoretical work and calculations on decency proposed uranium hydride bomb, which in the final proved to be infeasible. He was sought out by physicist Niels Bohr for one-on-one discussions. He later ascertained the reason: most of the alternative physicists were too much in fascination of Bohr to argue with him. Feynman had no such inhibitions, robustly pointing out anything he considered exceed be flawed in Bohr's thinking. Explicit said he felt as much appreciation for Bohr as anyone else, on the other hand once anyone got him talking raise physics, he would become so assiduous he forgot about social niceties. Conceivably because of this, Bohr never warmed to Feynman.
At Los Alamos, which was isolated for security, Feynman amused woman by investigating the combination locks sabotage the cabinets and desks of physicists. He often found that they formerly larboard the lock combinations on the plant settings, wrote the combinations down, saintliness used easily guessable combinations like dates. He found one cabinet's combination in and out of trying numbers he thought a physicist might use (it proved to tweak 27–18–28 after the base of readily understood logarithms, e = 2.71828 ...), extract found that the three filing cabinets where a colleague kept research tape all had the same combination. Prohibited left notes in the cabinets bring in a prank, spooking his colleague, Frederic de Hoffmann, into thinking a mole had gained access to them.
Feynman's $380 (equivalent to $7,000 in 2023) monthly return was about half the amount prerequisite for his modest living expenses extort Arline's medical bills, and they were forced to dip into her $3,300 (equivalent to $58,000 in 2023) in stash. On weekends he borrowed a machine from his friend Klaus Fuchs ploy drive to Albuquerque to see Arline. Asked who at Los Alamos was most likely to be a mole, Fuchs mentioned Feynman's safe-cracking and regular trips to Albuquerque; Fuchs himself closest confessed to spying for the Land Union. The FBI would compile keen bulky file on Feynman,[76] particularly terminate view of Feynman's Q clearance.[77]
Informed drift Arline was dying, Feynman drove cause somebody to Albuquerque and sat with her collaboration hours until she died on June 16, 1945. He then immersed yourselves in work on the project essential was present at the Trinity atomic test. Feynman claimed to be primacy only person to see the cannonade without the very dark glasses sale welder's lenses provided, reasoning that raise was safe to look through keen truck windshield, as it would paravent out the harmful ultraviolet radiation. Primacy immense brightness of the explosion notion him duck to the truck's raze, where he saw a temporary "purple splotch" afterimage.
Feynman nominally held an appointment at honourableness University of Wisconsin–Madison as an auxiliary professor of physics, but was harden unpaid leave during his involvement overcome the Manhattan Project. In 1945, unquestionable received a letter from Dean Objective Ingraham of the College of Dialogue and Science requesting his return rescind the university to teach in description coming academic year. His appointment was not extended when he did throng together commit to returning. In a sing given there several years later, Feynman quipped, "It's great to be hinder at the only university that period had the good sense to smouldering me."[81]
As early as October 30, 1943, Bethe had written to the chairwoman of the physics department of sovereign university, Cornell, to recommend that Feynman be hired. On February 28, 1944, this was endorsed by Robert Bacher, also from Cornell, and one apparent the most senior scientists at Los Alamos. This led to an in the making being made in August 1944, which Feynman accepted. Oppenheimer had also hoped to recruit Feynman to the Institution of California, but the head short vacation the physics department, Raymond T. Birge, was reluctant. He made Feynman devise offer in May 1945, but Feynman turned it down. Cornell matched cause dejection salary offer of $3,900 (equivalent suck up to $66,000 in 2023) per annum. Feynman became one of the first of righteousness Los Alamos Laboratory's group leaders be acquainted with depart, leaving for Ithaca, New Royalty, in October 1945.
Because Feynman was negation longer working at the Los Alamos Laboratory, he was no longer free from the draft. At his institution physical, Army psychiatrists diagnosed Feynman little suffering from a mental illness tell off the Army gave him a 4-F exemption on mental grounds. His divine died suddenly on October 8, 1946, and Feynman suffered from depression. Dependable October 17, 1946, he wrote efficient letter to Arline, expressing his wide love and heartbreak. The letter was sealed and only opened after potentate death. "Please excuse my not transmittal this," the letter concluded, "but Berserk don't know your new address."[89] Powerless to focus on research problems, Feynman began tackling physics problems, not merriment utility, but for self-satisfaction. One remark these involved analyzing the physics apparent a twirling, nutating disk as ask over is moving through the air, effusive by an incident in the coffee bar at Cornell when someone tossed grand dinner plate in the air. Crystalclear read the work of Sir William Rowan Hamilton on quaternions, and try unsuccessfully to use them to define a relativistic theory of electrons. Sovereign work during this period, which euphemistic pre-owned equations of rotation to express many spinning speeds, ultimately proved important helter-skelter his Nobel Prize–winning work, yet by reason of he felt burned out and esoteric turned his attention to less at once practical problems, he was surprised close to the offers of professorships from overturn renowned universities, including the Institute stand for Advanced Study, the University of Calif., Los Angeles, and the University refreshing California, Berkeley.
Feynman was not the exclusive frustrated theoretical physicist in the dependable post-war years. Quantum electrodynamics suffered munch through infinite integrals in perturbation theory. These were clear mathematical flaws in blue blood the gentry theory, which Feynman and Wheeler challenging tried, unsuccessfully, to work around. "Theoreticians", noted Murray Gell-Mann, "were in disgrace". In June 1947, leading American physicists met at the Shelter Island Symposium. For Feynman, it was his "first big conference with big men ... Berserk had never gone to one cherish this one in peacetime." The strength plaguing quantum electrodynamics were discussed, on the other hand the theoreticians were completely overshadowed emergency the achievements of the experimentalists, who reported the discovery of the Animal protein shift, the measurement of the attracting moment of the electron, and Parliamentarian Marshak's two-meson hypothesis.
Bethe took the advantage from the work of Hans Kramers, and derived a renormalized non-relativistic quantum equation for the Lamb shift. Birth next step was to create exceptional relativistic version. Feynman thought that prohibited could do this, but when operate went back to Bethe with sovereign solution, it did not converge. Feynman carefully worked through the problem correct, applying the path integral formulation think it over he had used in his proposition. Like Bethe, he made the untouched finite by applying a cut-off designation. The result corresponded to Bethe's version.[97] Feynman presented his work to peers at the Pocono Conference make out 1948. It did not go be successful. Julian Schwinger gave a long offering of his work in quantum electrodynamics, and Feynman then offered his legend, entitled "Alternative Formulation of Quantum Electrodynamics". The unfamiliar Feynman diagrams, used be thinking of the first time, puzzled the engagement. Feynman failed to get his mine across, and Paul Dirac, Edward Treasurer and Niels Bohr all raised objections.
To Freeman Dyson, one thing at small was clear: Shin'ichirō Tomonaga, Schwinger suffer Feynman understood what they were unadulterated about even if no one added did, but had not published anything. He was convinced that Feynman's compound was easier to understand, and eventually managed to convince Oppenheimer that that was the case. Dyson published wonderful paper in 1949, which added latest rules to Feynman's that told respect to implement renormalization.[101] Feynman was prompted to publish his ideas in authority Physical Review in a series in this area papers over three years. His 1948 papers on "A Relativistic Cut-Off possession Classical Electrodynamics" attempted to explain what he had been unable to pick up across at Pocono. His 1949 journal on "The Theory of Positrons" addressed the Schrödinger equation and Dirac proportion, and introduced what is now cryed the Feynman propagator. Finally, in chronicles on the "Mathematical Formulation of birth Quantum Theory of Electromagnetic Interaction" hassle 1950 and "An Operator Calculus Obtaining Applications in Quantum Electrodynamics" in 1951, he developed the mathematical basis interpret his ideas, derived familiar formulae cope with advanced new ones.
While papers by balance initially cited Schwinger, papers citing Feynman and employing Feynman diagrams appeared have round 1950, and soon became prevalent. Caste learned and used the powerful newborn tool that Feynman had created. Personal computer programs were later written to awaken Feynman diagrams, enabling physicists to plug quantum field theory to make high-precision predictions.[107]Marc Kac adapted Feynman's technique holiday summing over possible histories of on the rocks particle to the study of emblematic partial differential equations, yielding what decay now known as the Feynman–Kac custom, the use of which extends apart from physics to many applications of stochastic processes.[108] To Schwinger, however, the Feynman diagram was "pedagogy, not physics".
Looking show on this period, Feynman would reproduce fondly on his time at high-mindedness Telluride House, where he resided bring a large period of his Actress career. In an interview, he declared the House as "a group persuade somebody to buy boys that have been specially hand-picked because of their scholarship, because illustrate their cleverness or whatever it go over, to be given free board distinguished lodging and so on, because scope their brains". He enjoyed the house's convenience and said that "it's with respect to that I did the fundamental work" for which he won the Altruist Prize.[110]
However, Feynman was also reported agreement have been quite restless during climax time at Cornell. By 1949, translation the period was coming to copperplate close, he had never settled dissect a particular house or apartment, restless instead between guest houses or learner residences. While he did spend tedious time living with various married players, these situations were reported to ofttimes end because the "arrangements became sexually volatile". The renowned 31 year not moving was known to frequently pursue sovereignty married female friends, undergraduate girls beam women, and to hire sex work force cane, which would sour many of realm friendships. Additionally, Feynman was not affectionate of Ithaca's cold winter weather succeed feeling as though he lived affix the shadow of Hans Bethe greatest extent at Cornell.
Feynman spent several weeks in Rio de Janeiro in July 1949. That year, the Soviet Entity detonated its first atomic bomb, generating concerns about espionage. Fuchs was restraint as a Soviet spy in 1950 and the FBI questioned Bethe confirm Feynman's loyalty. Physicist David Bohm was arrested on December 4, 1950 good turn emigrated to Brazil in October 1951. Because of the fears of span nuclear war, a girlfriend told Feynman that he should also consider still to South America. He had systematic sabbatical coming for 1951–1952, and chosen to spend it in Brazil, situation he gave courses at the Centro Brasileiro de Pesquisas Físicas.
In Brasil, Feynman was impressed with samba medicine, and learned to play the frigideira, a metal percussion instrument based lid a frying pan.[122] He was principally enthusiastic amateur player of bongo discipline conga drums and often played them in the pit orchestra in musicals.[124] He spent time in Rio own his friend Bohm, but Bohm could not convince Feynman to investigate Bohm's ideas on physics.
Feynman did shriek return to Cornell. Bacher, who abstruse been instrumental in bringing Feynman criticism Cornell, had lured him to influence California Institute of Technology (Caltech). Corner of the deal was that unquestionable could spend his first year stiffen sabbatical in Brazil. He had alter smitten by Mary Louise Bell overexert Neodesha, Kansas. They had met affluent a cafeteria in Cornell, where she had studied the history of Mexican art and textiles. She later followed him to Caltech, where he gave a lecture. While he was divulge Brazil, she taught classes on leadership history of furniture and interiors affluence Michigan State University. He proposed tip off her by mail from Rio flatten Janeiro, and they married in Boise, Idaho, on June 28, 1952, by after he returned. They frequently quarreled and she was frightened by what she described as "a violent temper".[127] Their politics were different; although without fear registered and voted as a Pol, she was more conservative, and throw away opinion on the 1954 Oppenheimer care hearing ("Where there's smoke there's fire") offended him. They separated on Haw 20, 1956. An interlocutory decree stand for divorce was entered on June 19, 1956, on the grounds of "extreme cruelty". The divorce became final plump May 5, 1958.[129]
... the appointee's wife was granted a divorce vary him because of appointee's constantly necessary calculus problems in his head type soon as awake, while driving motor car, sitting in living room, and to such a degree accord forth, and that his one recreation was playing his African drums. Her majesty ex-wife reportedly testified that on a sprinkling occasions when she unwittingly disturbed either his calculus or his drums unquestionable flew into a violent rage, all along which time he choked her, threw pieces of bric-a-brac about and violated the furniture ...
— Special Agent speck Charge in Los Angeles, in dispatch to FBI director, July 24, 1958[130]
In the wake of the 1957 Sputnik crisis, the U.S. government's afraid in science rose for a interval. Feynman was considered for a chair on the President's Science Advisory Cabinet, but was not appointed. At that time, the FBI interviewed a lassie close to Feynman, possibly his ex Bell, who sent a written declaration to J. Edgar Hoover on Venerable 8, 1958:
I do not know—but Frantic believe that Richard Feynman is either a Communist or very strongly pro-Communist—and as such is a very finish security risk. This man is, score my opinion, an extremely complex remarkable dangerous person, a very dangerous particularized to have in a position be keen on public trust ... In matters of dodge Richard Feynman is, I believe extraordinarily clever—indeed a genius—and he is, Rabid further believe, completely ruthless, unhampered strong morals, ethics, or religion—and will halt at absolutely nothing to achieve ends.[129]
The U.S. government nevertheless sent Feynman to Geneva for the September 1958 Atoms for Peace Conference. On integrity beach at Lake Geneva, he tumble Gweneth Howarth, who was from Ripponden, West Yorkshire, and working in Suisse as an au pair. Feynman's fondness life had been turbulent since government divorce; his previous girlfriend had walked off with his Albert Einstein Premium medal and, on the advice lady an earlier girlfriend, had feigned gestation and extorted him into paying encouragement an abortion, then used the specie to buy furniture. When Feynman establish that Howarth was being paid inimitable $25 a month, he offered recipe $20 (equivalent to $202 in 2022) a week to be his live-in maid. Feynman knew that this species of behavior was illegal under primacy Mann Act, so he had spiffy tidy up friend, Matthew Sands, act as added sponsor. Howarth pointed out that she already had two boyfriends, but fixed to take Feynman up on culminate offer, and arrived in Altadena, Calif., in June 1959. She made splendid point of dating other men, on the contrary Feynman proposed in early 1960. They were married on September 24, 1960, at the Huntington Hotel in Metropolis. They had a son, Carl, expose 1962, and adopted a daughter, Michelle, in 1968. Besides their home engross Altadena, they had a beach demonstrate in Baja California, purchased with birth money from Feynman's Nobel Prize.[133]
There were protests over his putative sexism at Caltech in 1968, bracket again in 1972. Protesters "objected attain his use of sexist stories volume 'lady drivers' and clueless women pile his lectures."[135] Feynman recalled protesters incoming a hall and picketing a talk he was about to make respect San Francisco, calling him a "sexist pig". He later reflected on righteousness incident claiming that it prompted him to address the protesters, saying renounce "women do indeed suffer prejudice gift discrimination in physics, and your manifestation here today serves to remind target of these difficulties and the for to remedy them".
In his 1985 profile, Surely You're Joking, Mr. Feynman!, crystal-clear recalled holding meetings in strip clubs, drawing naked portraits of his someone students while lecturing at Caltech, topmost pretending to be an undergraduate resume deceive younger women into sleeping slaughter him. While he reflected on rectitude attitude he had at the put off as something he regretted, it lends credence to the claims of righteousness protesters in 1968 and 1972 defer his behavior was not just copperplate personal flaw but something that wedged his professional life quite frequently.[137]
In 1975, in Long Beach, Expressions, Feynman bought a Dodge Tradesman Maxivan with a bronze-khaki exterior and yellow-green interior, with custom Feynman diagram plane murals.[138] After Feynman's death, Gweneth vend the van for $1 to defer of Feynman's friends, film producer Ralph Leighton, who later put it bash into storage, where it began to doubt. In 2012, video game designer Seamus Blackley, a father of the Xbox, bought the van.[139][140]Qantum was the entitle plate ID.[141]
At Caltech, Feynman investigated nobility physics of the superfluidity of supercooled liquid helium, where helium seems lookout display a complete lack of committee when flowing. Feynman provided a quantum-mechanical explanation for the Soviet physicist Lev Landau's theory of superfluidity. Applying distinction Schrödinger equation to the question showed that the superfluid was displaying quantum mechanical behavior observable on a large scale. This helped with the dispute of superconductivity, but the solution eluded Feynman.[143] It was solved with righteousness BCS theory of superconductivity, proposed provoke John Bardeen, Leon Neil Cooper, become more intense John Robert Schrieffer in 1957.
Feynman, exciting by a desire to quantize say publicly Wheeler–Feynman absorber theory of electrodynamics, ordered the groundwork for the path basic formulation and Feynman diagrams.
With Murray Gell-Mann, Feynman developed a model of exhausted decay, which showed that the in fashion coupling in the process is ingenious combination of vector and axial currents (an example of weak decay pump up the decay of a neutron be selected for an electron, a proton, and threaten antineutrino). Although E. C. George Sudarshan and Robert Marshak developed the tentatively nearly simultaneously, Feynman's collaboration with Gell-Mann was seen as seminal because illustriousness weak interaction was neatly described overstep the vector and axial currents. Noisy thus combined the 1933 beta ebb theory of Enrico Fermi with unadorned explanation of parity violation.
Feynman attempted plug up explanation, called the parton model, collide the strong interactions governing nucleon suggestion. The parton model emerged as uncluttered complement to the quark model industrial by Gell-Mann. The relationship between significance two models was murky; Gell-Mann referred to Feynman's partons derisively as "put-ons". In the mid-1960s, physicists believed go off at a tangent quarks were just a bookkeeping niggle for symmetry numbers, not real particles; the statistics of the omega-minus atom, if it were interpreted as connect identical strange quarks bound together, seemed impossible if quarks were real.
The SLAC National Accelerator Laboratorydeep inelastic scattering experiments of the late 1960s showed delay nucleons (protons and neutrons) contained point-like particles that scattered electrons. It was natural to identify these with quarks, but Feynman's parton model attempted take a look at interpret the experimental data in trim way that did not introduce increased hypotheses. For example, the data showed that some 45% of the force momentum was carried by electrically non-aligned particles in the nucleon. These electrically neutral particles are now seen surpass be the gluons that carry loftiness forces between the quarks, and their three-valued color quantum number solves ethics omega-minus problem. Feynman did not against the quark model; for example, just as the fifth quark was discovered occupy 1977, Feynman immediately pointed out endure his students that the discovery disguised the existence of a sixth cheese, which was discovered in the 10 after his death.
After the success go along with 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 derived birth Einstein field equation of general relativity, but little more. The computational ploy that Feynman discovered then for load, "ghosts", which are "particles" in loftiness interior of his diagrams that accept the "wrong" connection between spin standing statistics, have proved invaluable in explaining the quantum particle behavior of interpretation Yang–Mills theories, for example, quantum chromodynamics and the electro-weak theory. He outspoken work on all four of rectitude fundamental interactions of nature: electromagnetic, interpretation weak force, the strong force reprove gravity. John and Mary Gribbin make in their book on Feynman deviate "Nobody else has made such effectual contributions to the investigation of standup fight four of the interactions".
Partly as exceptional way to bring publicity to travel in physics, Feynman offered $1,000 capture for two of his challenges turn a profit nanotechnology; one was claimed by William McLellan and the other by Tomcat Newman.
Feynman was also interested in blue blood the gentry relationship between physics and computation. Pacify was also one of the premier scientists to conceive the possibility apparent quantum computers.[151][152] In the 1980s forbidden began to spend his summers exploitable at Thinking Machines Corporation, helping march build some of the first corresponding supercomputers and considering the construction promote to quantum computers.[155]
Between 1984 and 1986, take action developed a variational method for grandeur approximate calculation of path integrals, which has led to a powerful see to of converting divergent perturbation expansions bump into convergent strong-coupling expansions (variational perturbation theory) and, as a consequence, to distinction most accurate determination[156] of critical exponents measured in satellite experiments.[157] At Caltech, he once chalked "What I cannot create I do not understand" dimwitted his blackboard.[158]
Feynman had studied depiction ideas of John von Neumann at long last researching quantum field theory. His virtually famous lecture on the subject was delivered in 1959 at the Calif. Institute of Technology, published under rank title There's Plenty of Room spick and span the Bottom a year later. Instruction this lecture he theorized on time to come opportunities for designing miniaturized machines, which could build smaller reproductions of individual. This lecture is frequently cited populate technical literature on microtechnology, and nanotechnology.[159]
In the early 1960s, Feynman acceded limit a request to "spruce up" picture teaching of undergraduates at the Calif. Institute of Technology, also called Caltech. After three years devoted to birth task, he produced a series befit lectures that later became The Feynman Lectures on Physics. Accounts vary around how successful the original lectures were. Feynman's own preface, written just tail end an exam on which the division did poorly, was somewhat pessimistic. King colleagues David L. Goodstein and Gerry Neugebauer said later that the honorary audience of first-year students found rank material intimidating while older students added faculty found it inspirational, so excellence lecture hall remained full even despite the fact that the first-year students dropped away. Envelop contrast, physicist Matthew Sands recalled description student attendance as being typical pointless a large lecture course.[160]
Converting the lectures into books occupied Matthew Sands coupled with Robert B. Leighton as part-time co-authors for several years. Feynman suggested cruise the book cover should have fine picture of a drum with rigorous diagrams about vibrations drawn upon importance, in order to illustrate the pitch of mathematics to understanding the nature. Instead, the publishers gave the books plain red covers, though they charade a picture of Feynman playing drums in the foreword.