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Saturday, January 24, 2015

Richard Feynman

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Richard Feynman
Richard Feynman Nobel.jpg
Born Richard Phillips Feynman
May 11, 1918
New York City
Died February 15, 1988 (aged 69)
Los Angeles, California
Residence United States
Nationality American
Fields Theoretical physics
Institutions Cornell University
California Institute of Technology
Alma mater Massachusetts Institute of Technology (B.S.),
Princeton University (Ph.D.)
Thesis The Principle of Least Action in Quantum Mechanics (1942)
Doctoral advisor John Archibald Wheeler[1]
Other academic advisors Manuel Sandoval Vallarta
Doctoral students F. L. Vernon, Jr.[1]
Willard H. Wells[1]
Al Hibbs[1]
George Zweig[1]
Giovanni Rossi Lomanitz[1]
Thomas Curtright[1]
James M. Bardeen
Other notable students Douglas D. Osheroff
Paul Steinhardt
Robert Barro
W. Daniel Hillis
Known for
Influences Paul Dirac
Influenced Freeman Dyson
Notable awards Albert Einstein Award (1954)
E. O. Lawrence Award (1962)
Nobel Prize in Physics (1965)
Oersted Medal (1972)
National Medal of Science (1979)
Spouse Arline Greenbaum (m. 1941–45)(deceased)
Mary Louise Bell (m. 1952–56)[2]
Gweneth Howarth (m. 1960–88) (his death)
Children Carl Feynman
Michelle Feynman
Signature

Richard Phillips Feynman (/ˈfnmən/; May 11, 1918 – February 15, 1988) was an American theoretical physicist known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics, and the physics of the superfluidity of supercooled liquid helium, as well as in particle physics (he proposed the parton model). For his contributions to the development of quantum electrodynamics, Feynman, jointly with Julian Schwinger and Sin-Itiro Tomonaga, received the Nobel Prize in Physics in 1965. He developed a widely used pictorial representation scheme for the mathematical expressions governing the behavior of subatomic particles, which later became known as Feynman diagrams. During his lifetime, Feynman became one of the best-known scientists in the world. In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World he was ranked as one of the ten greatest physicists of all time.[3]

He assisted in the development of the atomic bomb during World War II and became known to a wide public in the 1980s as a member of the Rogers Commission, the panel that investigated the Space Shuttle Challenger disaster. In addition to his work in theoretical physics, Feynman has been credited with pioneering the field of quantum computing,[4][5] and introducing the concept of nanotechnology. He held the Richard Chace Tolman professorship in theoretical physics at the California Institute of Technology.

Feynman was a keen popularizer of physics through both books and lectures, notably a 1959 talk on top-down nanotechnology called There's Plenty of Room at the Bottom, and the three-volume publication of his undergraduate lectures, The Feynman Lectures on Physics. Feynman also became known through his semi-autobiographical books Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think? and books written about him, such as Tuva or Bust!.

Early life

Richard Phillips Feynman was born on May 11, 1918, in New York City,[6][7] the son of Lucille (née Phillips), a homemaker, and Melville Arthur Feynman, a sales manager.[8] His family originated from Russia and Poland; both of his parents were Ashkenazi Jews.[9] They were not religious, and by his youth Feynman described himself as an "avowed atheist".[10]

Feynman was a late talker, and by his third birthday had yet to utter a single word. He would retain a Bronx accent as an adult.[11][12] That accent was thick enough to be perceived as an affectation or exaggeration[13][14] — so much so that his good friends Wolfgang Pauli and Hans Bethe would one day comment that Feynman spoke like a "bum".[13]

The young Feynman was heavily influenced by his father, who encouraged him to ask questions to challenge orthodox thinking, and who was always ready to teach Feynman something new. From his mother he gained the sense of humor that he had throughout his life. As a child, he had a talent for engineering, maintained an experimental laboratory in his home, and delighted in repairing radios. When he was in grade school, he created a home burglar alarm system while his parents were out for the day running errands.[15]

When Richard was five years old, his mother gave birth to a younger brother, but this brother died at four weeks of age. Four years later, Richard gained a sister, Joan, and the family moved to Far Rockaway, Queens.[8] Though separated by nine years, Joan and Richard were close, as they both shared a natural curiosity about the world. Their mother thought that women did not have the cranial capacity to comprehend such things. Despite their mother's disapproval of Joan's desire to study astronomy, Richard encouraged his sister to explore the universe. Joan eventually became an astrophysicist specializing in interactions between the Earth and the solar wind.[16]

Education

Upon starting high school, Feynman was quickly promoted into a higher math class and an unspecified school-administered IQ test estimated his IQ at 125—high, but "merely respectable" according to biographer James Gleick;[17] In 1933, when he turned 15, he taught himself trigonometry, advanced algebra, infinite series, analytic geometry, and both differential and integral calculus.[18] Before entering college, he was experimenting with and deriving mathematical topics such as the half-derivative using his own notation. In high school he was developing the mathematical intuition behind his Taylor series of mathematical operators.

His habit of direct characterization sometimes rattled more conventional thinkers; for example, one of his questions, when learning feline anatomy, was "Do you have a map of the cat?" (referring to an anatomical chart).[19]

Feynman attended Far Rockaway High School, a school also attended by fellow laureates Burton Richter and Baruch Samuel Blumberg.[20] A member of the Arista Honor Society, in his last year in high school Feynman won the New York University Math Championship; the large difference between his score and those of his closest competitors shocked the judges.

He applied to Columbia University but was not accepted because of their quota for the number of Jews admitted.[8][21] Instead, he attended the Massachusetts Institute of Technology, where he received a bachelor's degree in 1939 and in the same year was named a Putnam Fellow.[22]

He attained a perfect score on the graduate school entrance exams to Princeton University in mathematics and physics—an unprecedented feat—but did rather poorly on the history and English portions.[23] Attendees at Feynman's first seminar included Albert Einstein, Wolfgang Pauli, and John von Neumann. He received a Ph.D. from Princeton in 1942; his thesis advisor was John Archibald Wheeler. Feynman's thesis applied the principle of stationary action to problems of quantum mechanics, inspired by a desire to quantize the Wheeler–Feynman absorber theory of electrodynamics, laying the groundwork for the "path integral" approach and Feynman diagrams, and was titled "The Principle of Least Action in Quantum Mechanics".
This was Richard Feynman nearing the crest of his powers. At twenty-three … there was no physicist on earth who could match his exuberant command over the native materials of theoretical science. It was not just a facility at mathematics (though it had become clear … that the mathematical machinery emerging from the Wheeler–Feynman collaboration was beyond Wheeler's own ability). Feynman seemed to possess a frightening ease with the substance behind the equations, like Albert Einstein at the same age, like the Soviet physicist Lev Landau—but few others.

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

Manhattan Project

Feynman (center) with Robert Oppenheimer (right) relaxing at a Los Alamos social function during 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 build it before Nazi Germany developed their own bomb. He was assigned to Hans Bethe's theoretical division and impressed Bethe enough to be made a group leader. He and Bethe developed the Bethe–Feynman formula for calculating the yield of a fission bomb, which built upon previous work by Robert Serber.

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 or welder's lenses provided, reasoning that it was safe to look through a truck windshield, as it would screen out the harmful ultraviolet radiation. On witnessing the blast, Feynman ducked towards the floor of his truck because of the immense brightness of the explosion, where he saw a temporary "purple splotch" afterimage of the event.[24]

As a junior physicist, he was not central to the project. The greater part of his work was administering the computation group of human computers in the theoretical division (one of his students there, John G. Kemeny, later went on to co-design and co-specify the programming language BASIC). Later, with Nicholas Metropolis, he assisted in establishing the system for using IBM punched cards for computation.

Feynman's other work at Los Alamos included calculating neutron equations for the Los Alamos "Water Boiler", a small nuclear reactor, to measure how close an assembly of fissile material was to criticality. On completing this work he was transferred to the Oak Ridge facility, where he aided engineers in devising safety procedures for material storage so that criticality accidents (for example, due to sub-critical amounts of fissile material inadvertently stored in proximity on opposite sides of a wall) could be avoided. He also did theoretical work and calculations on the proposed uranium hydride bomb, which later proved not to be feasible.

Feynman was sought out by physicist Niels Bohr for one-on-one discussions. He later discovered the reason: most of the other physicists were too much in awe of Bohr to argue with him. Feynman had no such inhibitions, vigorously pointing out anything he considered to be flawed in Bohr's thinking. Feynman said he felt as much respect for Bohr as anyone else, but once anyone got him talking about physics, he would become so focused he forgot about social niceties.

Due to the top secret nature of the work, Los Alamos was isolated. In Feynman's own words, "There wasn't anything to do there". Bored, he indulged his curiosity by learning to pick the combination locks on cabinets and desks used to secure papers. Feynman played many jokes on colleagues. In one case he found the combination to a locked filing cabinet by trying the numbers he thought a physicist would use (it proved to be 27–18–28 after the base of natural logarithms, e = 2.71828…), and found that the three filing cabinets where a colleague kept a set of atomic bomb research notes all had the same combination.[25] He left a series of notes in the cabinets as a prank, which initially spooked his colleague, Frederic de Hoffmann, into thinking a spy or saboteur had gained access to atomic bomb secrets. On several occasions, Feynman drove to Albuquerque to see his ailing wife in a car borrowed from Klaus Fuchs, who was later discovered to be a real spy for the Soviets, transporting nuclear secrets in his car to Santa Fe.

On occasion, Feynman would find an isolated section of the mesa where he could drum in the style of American natives; "and maybe I would dance and chant, a little". These antics did not go unnoticed, and rumors spread about a mysterious Indian drummer called "Injun Joe". He also became a friend of the laboratory head, J. Robert Oppenheimer, who unsuccessfully tried to court him away from his other commitments after the war to work at the University of California, Berkeley.

Feynman alludes to his thoughts on the justification for getting involved in the Manhattan project in The Pleasure of Finding Things Out. He felt the possibility of Nazi Germany developing the bomb before the Allies was a compelling reason to help with its development for the U.S. He goes on to say, however, that it was an error on his part not to reconsider the situation once Germany was defeated. In the same publication, Feynman also talks about his worries in the atomic bomb age, feeling for some considerable time that there was a high risk that the bomb would be used again soon, so that it was pointless to build for the future. Later he describes this period as a "depression."

Early academic career

Following the completion of his Ph.D. in 1942, Feynman held an appointment at the University of Wisconsin–Madison as an assistant professor of physics. The appointment was spent on leave for his involvement in the Manhattan project. In 1945, he received a letter from Dean Mark Ingraham of the College of Letters and Science requesting his return to UW to teach in the coming academic year. His appointment was not extended when he did not commit to return. In a talk given several years later at UW, Feynman quipped, "It's great to be back at the only university that ever had the good sense to fire me".[26]

After the war, Feynman declined an offer from the Institute for Advanced Study in Princeton, New Jersey, despite the presence there of such distinguished faculty members as Albert Einstein, Kurt Gödel and John von Neumann. Feynman followed Hans Bethe, instead, to Cornell University, where Feynman taught theoretical physics from 1945 to 1950. During a temporary depression following the destruction of Hiroshima by the bomb produced by the Manhattan Project, he focused on complex physics problems, not for utility, but for self-satisfaction. One of these was analyzing the physics of a twirling, nutating dish as it is moving through the air. His work during this period, which used equations of rotation to express various spinning speeds, proved important to his Nobel Prize-winning work, yet because he felt burned out and had turned his attention to less immediately practical problems, he was surprised by the offers of professorships from other renowned universities.

Despite yet another offer from the Institute for Advanced Study, Feynman rejected the Institute on the grounds that there were no teaching duties: Feynman felt that students were a source of inspiration and teaching was a diversion during uncreative spells. Because of this, the Institute for Advanced Study and Princeton University jointly offered him a package whereby he could teach at the university and also be at the institute.[citation needed] Feynman instead accepted an offer from the California Institute of Technology (Caltech)—and as he says in his book Surely You're Joking Mr. Feynman!—because a desire to live in a mild climate had firmly fixed itself in his mind while he was installing tire chains on his car in the middle of a snowstorm in Ithaca.

Feynman has been called the "Great Explainer".[27] He gained a reputation for taking great care when giving explanations to his students and for making it a moral duty to make the topic accessible. His guiding principle was that, if a topic could not be explained in a freshman lecture, it was not yet fully understood. Feynman gained great pleasure [28] from coming up with such a "freshman-level" explanation, for example, of the connection between spin and statistics. What he said was that groups of particles with spin ½ "repel", whereas groups with integer spin "clump." This was a brilliantly simplified way of demonstrating how Fermi–Dirac statistics and Bose–Einstein statistics evolved as a consequence of studying how fermions and bosons behave under a rotation of 360°. This was also a question he pondered in his more advanced lectures, and to which he demonstrated the solution in the 1986 Dirac memorial lecture.[29] In the same lecture, he further explained that antiparticles must exist, for if particles had only positive energies, they would not be restricted to a so-called "light cone."

He opposed rote learning or unthinking memorization and other teaching methods that emphasized form over function. Clear thinking and clear presentation were fundamental prerequisites for his attention. It could be perilous even to approach him when unprepared, and he did not forget the fools or pretenders.[30]

Caltech years

The Feynman section at the Caltech bookstore

Feynman did significant work while at Caltech, including research in:
  • Quantum electrodynamics. The theory for which Feynman won his Nobel Prize is known for its accurate predictions.[31] This theory was begun in the earlier years during Feynman's work at Princeton as a graduate student and continued while he was at Cornell. This work consisted of two distinct formulations, and it is a common error to confuse them or to merge them into one. The first is his path integral formulation (actually, Feynman couldn't formulate QED as a Feynman Integral since that involves super-Feynman Integrals which were developed by others in the 50's), and the second is the formulation of his Feynman diagrams. Both formulations contained his sum over histories method in which every possible path from one state to the next is considered, the final path being a sum over the possibilities (also referred to as sum-over-paths).[32] For a number of years he lectured to students at Caltech on his path integral formulation of quantum theory. The second formulation of quantum electrodynamics (using Feynman diagrams) was specifically mentioned by the Nobel committee. The logical connection with the path integral formulation is interesting. Feynman did not prove that the rules for his diagrams followed mathematically from the path integral formulation. Some special cases were later proved by other people, but only in the real case, so the proofs don't work when spin is involved. The second formulation should be thought of as starting anew, but guided by the intuitive insight provided by the first formulation. Freeman Dyson published a paper in 1949 which, among many other things, added new rules to Feynman's which told how to actually implement renormalization. Students everywhere learned and used the powerful new tool that Feynman had created. Eventually computer programs were written to compute Feynman diagrams, providing a tool of unprecedented power. It is possible to write such programs because the Feynman diagrams constitute a formal language with a grammar. Marc Kac provided the formal proofs of the summation under history, showing that the parabolic partial differential equation can be reexpressed as a sum under different histories (that is, an expectation operator), what is now known as the Feynman-Kac formula, the use of which extends beyond physics to many applications of stochastic processes.[33]
  • Physics of the superfluidity of supercooled liquid helium, where helium seems to display a complete lack of viscosity when flowing. Feynman provided a quantum-mechanical explanation for the Soviet physicist Lev D. Landau’s theory of superfluidity.[34] Applying the Schrödinger equation to the question showed that the superfluid was displaying quantum mechanical behavior observable on a macroscopic scale. This helped with the problem of superconductivity; however, the solution eluded Feynman.[35] It was solved with the BCS theory of superconductivity, proposed by John Bardeen, Leon Neil Cooper, and John Robert Schrieffer.
  • A model of weak decay, which showed that the current coupling in the process is a combination of vector and axial currents (an example of weak decay is the decay of a neutron into an electron, a proton, and an anti-neutrino). Although E. C. George Sudarshan and Robert Marshak developed the theory nearly simultaneously, Feynman's collaboration with Murray Gell-Mann was seen as seminal because the weak interaction was neatly described by the vector and axial currents. It thus combined the 1933 beta decay theory of Enrico Fermi with an explanation of parity violation.
He also developed Feynman diagrams, a bookkeeping device which helps in conceptualizing and calculating interactions between particles in spacetime, notably the interactions between electrons and their antimatter counterparts, positrons. This device allowed him, and later others, to approach time reversibility and other fundamental processes. 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. Feynman famously painted Feynman diagrams on the exterior of his van.[36][37]

From his diagrams of a small number of particles interacting in spacetime, Feynman could then model all of physics in terms of the spins of those particles and the range of coupling of the fundamental forces.[38] Feynman attempted an explanation of the strong interactions governing nucleons scattering called the parton model. The parton model emerged as a complement to the quark model developed by his Caltech colleague Murray Gell-Mann. The relationship between the two models was murky; Gell-Mann referred to Feynman's partons derisively as "put-ons". In the mid-1960s, physicists believed that quarks were just a bookkeeping device for symmetry numbers, not real particles, as the statistics of the Omega-minus particle, if it were interpreted as three identical strange quarks bound together, seemed impossible if quarks were real. The Stanford linear accelerator deep inelastic scattering experiments of the late 1960s showed, analogously to Ernest Rutherford's experiment of scattering alpha particles on gold nuclei in 1911, that nucleons (protons and neutrons) contained point-like particles which scattered electrons. It was natural to identify these with quarks, but Feynman's parton model attempted to interpret the experimental data in a way which did not introduce additional hypotheses. For example, the data showed that some 45% of the energy momentum was carried by electrically-neutral particles in the nucleon. These electrically-neutral particles are now seen to be the gluons which carry the forces between the quarks and carry also the three-valued color quantum number which solves the Omega-minus problem. Feynman did not dispute the quark model; for example, when the fifth quark was discovered in 1977, Feynman immediately pointed out to his students that the discovery implied the existence of a sixth quark, which was duly discovered in the decade after his death.

After the success of quantum electrodynamics, Feynman turned to quantum gravity. By analogy with the photon, which has spin 1, he investigated the consequences of a free massless spin 2 field, and derived the Einstein field equation of general relativity, but little more.[39] However, the computational device that Feynman discovered then for gravity, "ghosts", which are "particles" in the interior of his diagrams which have the "wrong" connection between spin and statistics, have proved invaluable in explaining the quantum particle behavior of the Yang–Mills theories, for example, QCD and the electro-weak theory.
Mention of Feynman's prize on the monument at the American Museum of Natural History in New York City. Because the monument is dedicated to American Laureates, Tomonaga is not mentioned.

In 1965, Feynman was appointed a foreign member of the Royal Society.[6][40] At this time in the early 1960s, Feynman exhausted himself by working on multiple major projects at the same time, including a request, while at Caltech, to "spruce up" the teaching of undergraduates. After three years devoted to the task, he produced a series of lectures that eventually became The Feynman Lectures on Physics. He wanted a picture of a drumhead sprinkled with powder to show the modes of vibration at the beginning of the book. Concerned over the connections to drugs and rock and roll that could be made from the image, the publishers changed the cover to plain red, though they included a picture of him playing drums in the foreword. The Feynman Lectures on Physics [41] occupied two physicists, Robert B. Leighton and Matthew Sands, as part-time co-authors for several years. Even though the books were not adopted by most universities as textbooks, they continue to sell well because they provide a deep understanding of physics. As of 2005, The Feynman Lectures on Physics has sold over 1.5 million copies in English, an estimated 1 million copies in Russian, and an estimated half million copies in other languages.[citation needed] Many of his lectures and miscellaneous talks were turned into other books, including The Character of Physical Law, QED: The Strange Theory of Light and Matter, Statistical Mechanics, Lectures on Gravitation, and the Feynman Lectures on Computation.

Feynman's students competed keenly for his attention; he was once awakened when a student solved a problem and dropped it in his mailbox; glimpsing the student sneaking across his lawn, he could not go back to sleep, and he read the student's solution. The next morning his breakfast was interrupted by another triumphant student, but Feynman informed him that he was too late.

Partly as a way to bring publicity to progress in physics, Feynman offered $1,000 prizes for two of his challenges in nanotechnology; one was claimed by William McLellan and the other by Tom Newman.[42] He was also one of the first scientists to conceive the possibility of quantum computers.

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 "a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty" 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."[43]
Richard Feynman at the Robert Treat Paine Estate in Waltham, MA, in 1984.

In 1984–86, he developed a variational method for the approximate calculation of path integrals which has led to a powerful method of converting divergent perturbation expansions into convergent strong-coupling expansions (variational perturbation theory) and, as a consequence, to the most accurate determination[44] of critical exponents measured in satellite experiments.[45]

In the late 1980s, according to "Richard Feynman and the Connection Machine", Feynman played a crucial role in developing the first massively parallel computer, and in finding innovative uses for it in numerical computations, in building neural networks, as well as physical simulations using cellular automata (such as turbulent fluid flow), working with Stephen Wolfram at Caltech.[46] His son Carl also played a role in the development of the original Connection Machine engineering; Feynman influencing the interconnects while his son worked on the software.

Feynman diagrams are now fundamental for string theory and M-theory, and have even been extended topologically.[47] The world-lines of the diagrams have developed to become tubes to allow better modeling of more complicated objects such as strings and membranes. Shortly before his death, Feynman criticized string theory in an interview: "I don't like that they're not calculating anything," he said. "I don't like that they don't check their ideas. I don't like that for anything that disagrees with an experiment, they cook up an explanation—a fix-up to say, ‘Well, it still might be true.'" These words have since been much-quoted by opponents of the string-theoretic direction for particle physics.[34]

Challenger disaster


Feynman played an important role on the Presidential Rogers Commission, which investigated the Challenger disaster. During a televised hearing, Feynman demonstrated that the material used in the shuttle's O-rings became less resilient in cold weather by compressing a sample of the material in a clamp and immersing it in ice-cold water.[48] The commission ultimately determined that the disaster was caused by the primary O-ring not properly sealing in unusually cold weather at Cape Canaveral.[49]

Feynman devoted the latter half of his book What Do You Care What Other People Think? to his experience on the Rogers Commission, straying from his usual convention of brief, light-hearted anecdotes to deliver an extended and sober narrative. Feynman's account reveals a disconnect between NASA's engineers and executives that was far more striking than he expected. His interviews of NASA's high-ranking managers revealed startling misunderstandings of elementary concepts. For instance, NASA managers claimed that there was a 1 in 100,000 chance of a catastrophic failure aboard the shuttle, but Feynman discovered that NASA's own engineers estimated the chance of a catastrophe at closer to 1 in 200. He concluded that the space shuttle reliability estimate by NASA management was fantastically unrealistic, and he was particularly angered that NASA used these figures to recruit Christa McAuliffe into the Teacher-in-Space program. He warned in his appendix to the commission's report (which was included only after he threatened not to sign the report), "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled."[50]

A television documentary drama named The Challenger (US title: The Challenger Disaster), detailing Feynman's part in the investigation, was aired in 2013.[51]

Cultural identification

Although born to and raised by parents who were Ashkenazi, Feynman was not only an atheist,[52] but declined to be labelled Jewish. He routinely refused to be included in lists or books that classified people by race. He asked to not be included in Tina Levitan's The Laureates: Jewish Winners of the Nobel Prize, writing, "To select, for approbation the peculiar elements that come from some supposedly Jewish heredity is to open the door to all kinds of nonsense on racial theory," and adding "...at thirteen I was not only converted to other religious views, but I also stopped believing that the Jewish people are in any way 'the chosen people'".[53]

Personal life

While researching for his Ph.D., Feynman married his first wife, Arline Greenbaum (often misspelled Arlene). They married knowing that Arline was seriously ill from tuberculosis, of which she died in 1945. In 1946, Feynman wrote a letter to her, but kept it sealed for the rest of his life.[54] This portion of Feynman's life was portrayed in the 1996 film Infinity, which featured Feynman's daughter, Michelle, in a cameo role.

He married a second time in June 1952, to Mary Louise Bell of Neodesha, Kansas; this marriage was unsuccessful:
He begins working calculus problems in his head as soon as he awakens. He did calculus while driving in his car, while sitting in the living room, and while lying in bed at night.
—Mary Louise Bell divorce complaint[2]
He later married Gweneth Howarth (1934–1989) from Ripponden, Yorkshire, who shared his enthusiasm for life and spirited adventure.[36] Besides their home in Altadena, California, they had a beach house in Baja California, purchased with the prize money from Feynman's Nobel Prize, his one third share of $55,000. They remained married until Feynman's death. They had a son, Carl, in 1962, and adopted a daughter, Michelle, in 1968.[36]

Feynman had a great deal of success teaching Carl, using, for example, discussions about ants and Martians as a device for gaining perspective on problems and issues. He was surprised to learn that the same teaching devices were not useful with Michelle.[37] 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 co-worker characterized Feynman as akin to Don Quixote at his desk, rather than at a computer workstation, ready to do battle with the windmills.

Feynman traveled widely, notably to Brazil, where he gave courses at the CBPF (Brazilian Center for Physics Research) and near the end of his life schemed to visit the Russian land of Tuva, a dream that, because of Cold War bureaucratic problems, never became reality.[55] The day after he died, a letter arrived for him from the Soviet government, giving him authorization to travel to Tuva. Out of his enthusiastic interest in reaching Tuva came the phrase "Tuva or Bust" (also the title of a book about his efforts to get there), which was tossed about frequently amongst his circle of friends in hope that they, one day, could see it firsthand. The documentary movie, Genghis Blues, mentions some of his attempts to communicate with Tuva and chronicles the successful journey there by his friends.

Responding to Hubert Humphrey's congratulation for his Nobel Prize, Feynman admitted to a long admiration for the then vice president.[56] In a letter to an MIT professor dated December 6, 1966, Feynman expressed interest in running for governor of California.[57]

Feynman took up drawing at one time and enjoyed some success under the pseudonym "Ofey", culminating in an exhibition of his work. He learned to play a metal percussion instrument (frigideira) in a samba style in Brazil, and participated in a samba school.

In addition, he had some degree of synesthesia for equations, explaining that the letters in certain mathematical functions appeared in color for him, even though invariably printed in standard black-and-white.[58]

According to Genius, the James Gleick-authored biography, Feynman tried LSD during his professorship at Caltech.[34] Somewhat embarrassed by his actions, he largely sidestepped the issue when dictating his anecdotes; he mentions it in passing in the "O Americano, Outra Vez" section, while the "Altered States" chapter in Surely You're Joking, Mr. Feynman! describes only marijuana and ketamine experiences at John Lilly's famed sensory deprivation tanks, as a way of studying consciousness.[25] Feynman gave up alcohol when he began to show vague, early signs of alcoholism, as he did not want to do anything that could damage his brain—the same reason given in "O Americano, Outra Vez" for his reluctance to experiment with LSD.[25]

In Surely You're Joking, Mr. Feynman!, he gives advice on the best way to pick up a girl in a hostess bar. At Caltech, he used a nude or topless bar as an office away from his usual office, making sketches or writing physics equations on paper placemats. When the county officials tried to close the place, all visitors except Feynman refused to testify in favor of the bar, fearing that their families or patrons would learn about their visits. Only Feynman accepted, and in court, he affirmed that the bar was a public need, stating that craftsmen, technicians, engineers, common workers, "and a physics professor" frequented the establishment. While the bar lost the court case, it was allowed to remain open as a similar case was pending appeal.[25]

Feynman has a minor acting role in the film Anti-Clock credited as "The Professor".[59]

Death

Feynman had two rare forms of cancer, liposarcoma and Waldenström's macroglobulinemia, dying shortly after a final attempt at surgery for the former on February 15, 1988, aged 69.[34] His last recorded words are noted as, "I'd hate to die twice. It's so boring."[34][60]

Popular legacy

Actor Alan Alda commissioned playwright Peter Parnell to write a two-character play about a fictional day in the life of Feynman set two years before Feynman's death. The play, QED, which was based on writings about Richard Feynman's life during the 1990s, premiered at the Mark Taper Forum in Los Angeles, California in 2001. The play was then presented at the Vivian Beaumont Theater on Broadway, with both presentations starring Alda as Richard Feynman.[61]

On May 4, 2005, the United States Postal Service issued the American Scientists commemorative set of four 37-cent self-adhesive stamps in several configurations. The scientists depicted were Richard Feynman, John von Neumann, Barbara McClintock, and Josiah Willard Gibbs. Feynman's stamp, sepia-toned, features a photograph of a 30-something Feynman and eight small Feynman diagrams.[62] The stamps were designed by Victor Stabin under the artistic direction of Carl T. Herrman.[63]

The main building for the Computing Division at Fermilab is named the "Feynman Computing Center" in his honor.[64]

The principal character in Thomas A. McMahon's 1970 novel, Principles of American Nuclear Chemistry: A Novel, is modeled on Feynman.[citation needed]

Real Time Opera premiered its opera Feynman at the Norfolk (CT) Chamber Music Festival in June 2005.[65]

In February 2008 LA Theatre Works released a recording of 'Moving Bodies' with Alfred Molina in the role of Richard Feynman. This radio play written by playwright Arthur Giron is an interpretation on how Feynman became one of the iconic American scientists and is loosely based on material found in Feynman's two transcribed oral memoirs Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think?.

On the twentieth anniversary of Feynman's death, composer Edward Manukyan dedicated a piece for solo clarinet to his memory.[66] It was premiered by Doug Storey, the principal clarinetist of the Amarillo Symphony.

Between 2009 and 2011, clips of an interview with Feynman were used by composer John Boswell as part of the Symphony of Science project in the second, fifth, seventh, and eleventh installments of his videos, "We Are All Connected", "The Poetry of Reality", "A Wave of Reason", and "The Quantum World".[67]

In a 1992 New York Times article on Feynman and his legacy, James Gleick recounts the story of how Murray Gell-Mann described what has become known as "The Feynman Algorithm" or "The Feynman Problem-Solving Algorithm" to a student: "The student asks Gell-Mann about Feynman's notes. Gell-Mann says no, Dick's methods are not the same as the methods used here. The student asks, well, what are Feynman's methods? Gell-Mann leans coyly against the blackboard and says: Dick's method is this. You write down the problem. You think very hard. (He shuts his eyes and presses his knuckles parodically to his forehead.) Then you write down the answer." [68]

In 1998, a photograph of Richard Feynman giving a lecture was part of the poster series commissioned by Apple Inc. for their "Think Different" advertising campaign.[69]

In 2011, Feynman was the subject of a biographical graphic novel entitled simply Feynman, written by Jim Ottaviani and illustrated by Leland Myrick.[70]

In 2013, the BBC drama The Challenger depicted Feynman's role on the Rogers Commission in exposing the O-ring flaw in NASA's solid-rocket boosters (SRBs), itself based in part on Feynman's book What Do You Care What Other People Think?[71][72]

Bibliography

Selected scientific works

Textbooks and lecture notes

The Feynman Lectures on Physics is perhaps his most accessible work for anyone with an interest in physics, compiled from lectures to Caltech undergraduates in 1961–64. As news of the lectures' lucidity grew, a number of professional physicists and graduate students began to drop in to listen. Co-authors Robert B. Leighton and Matthew Sands, colleagues of Feynman, edited and illustrated them into book form. The work has endured and is useful to this day. They were edited and supplemented in 2005 with "Feynman's Tips on Physics: A Problem-Solving Supplement to the Feynman Lectures on Physics" by Michael Gottlieb and Ralph Leighton (Robert Leighton's son), with support from Kip Thorne and other physicists.

Popular works

Audio and video recordings

  • Safecracker Suite (a collection of drum pieces interspersed with Feynman telling anecdotes)
  • Los Alamos From Below (audio, talk given by Feynman at Santa Barbara on February 6, 1975)
  • Six Easy Pieces (original lectures upon which the book is based)
  • Six Not So Easy Pieces (original lectures upon which the book is based)
  • The Feynman Lectures on Physics: The Complete Audio Collection
  • Samples of Feynman's drumming, chanting and speech are included in the songs "Tuva Groove (Bolur Daa-Bol, Bolbas Daa-Bol)" and "Kargyraa Rap (Dürgen Chugaa)" on the album Back Tuva Future, The Adventure Continues by Kongar-ool Ondar. The hidden track on this album also includes excerpts from lectures without musical background.
  • The Messenger Lectures, given at Cornell in 1964, in which he explains basic topics in physics. Available on Project Tuva for free (See also the book The Character of Physical Law)
  • Take the world from another point of view [videorecording] / with Richard Feynman; Films for the Hu (1972)
  • The Douglas Robb Memorial Lectures Four public lectures of which the four chapters of the book QED: The Strange Theory of Light and Matter are transcripts. (1979)
  • The Pleasure of Finding Things Out on YouTube (1981) (not to be confused with the later published book of same title)
  • Richard Feynman: Fun to Imagine Collection, BBC Archive of 6 short films of Feynman talking in a style that is accessible to all about the physics behind common to all experiences. (1983)
  • Elementary Particles and the Laws of Physics (1986)
  • Tiny Machines: The Feynman Talk on Nanotechnology (video, 1984)
  • Computers From the Inside Out (video)
  • Quantum Mechanical View of Reality: Workshop at Esalen (video, 1983)
  • Idiosyncratic Thinking Workshop (video, 1985)
  • Bits and Pieces — From Richard's Life and Times (video, 1988)
  • Strangeness Minus Three (video, BBC Horizon 1964)
  • No Ordinary Genius (video, Cristopher Sykes Documentary)
  • Richard Feynman — The Best Mind Since Einstein (video, Documentary)
  • The Motion of Planets Around the Sun (audio, sometimes titled "Feynman's Lost Lecture")
  • Nature of Matter (audio)

Falcon Heavy

From Wikipedia, the free encyclopedia
 
Falcon Heavy
Falcon Heavy drawing.svg
Drawing of the Falcon Heavy reusable (left) and expendable (right) configurations
 
Function Orbital launch vehicle and potential Lunar launch vehicle[1]
Manufacturer SpaceX
Country of origin United States
Cost per launch (2015) $85M for up to 6,400 kg to GTO
Size
Height 68.4 m (224 ft)
Diameter 3.66 m (12.0 ft)
Mass 1,462,836 kg (3,225,001 lb)
Stages 2+
Capacity
Payload to LEO 53,000 kg (117,000 lb)
Payload to
GTO
21,200 kg (46,700 lb)
Launch history
Status In Development
Launch sites KSC LC-39A
Vandenberg SLC-4E[2]
Total launches 0
Successes 0
Failures 0
First flight 2015 (projected)
Boosters (Stage 0)
No. boosters 2
Engines 9 Merlin 1D
Thrust 5,880 kN (1,323,000 lbf)(sl)
Total thrust 17,615 kN (3,960,000 lbf) (total sea-level thrust of boosters plus core)[3]
Specific impulse Sea level: 282 sec
Vacuum: 311 sec
Burn time Unknown
Fuel LOX/RP-1
First stage
Engines 9 Merlin 1D
Thrust 5,880 kN (1,323,000 lbf)(sl)
Specific impulse Sea level: 282 sec
Vacuum: 311 sec
Burn time
Fuel LOX/RP-1
Second stage
Engines 1 Merlin 1D Vacuum
Thrust 801 kN (180,000 lbf)
Specific impulse Vacuum: 342 sec [4]
Burn time 375 seconds[5]
Fuel LOX/RP-1
 
Falcon Heavy (FH), previously known as the Falcon 9 Heavy, is a spaceflight launch system being designed and manufactured by SpaceX. The Falcon Heavy is a variant of the Falcon 9 v1.1 launch vehicle and will consist of a standard Falcon 9 rocket core, with two additional Falcon 9 first stages as strap-on boosters[6] – this will increase the low Earth orbit (LEO) payload to about 53 tonnes, compared to about 13 tonnes for a Falcon 9. The first launch is expected in 2015.[7]
SpaceX breaking ground at Vandenberg AFB SLC-4E for the Falcon Heavy launch pad

At a press conference at the National Press Club in Washington, DC. on 5 April 2011, Elon Musk stated, “Falcon Heavy will carry more payload to orbit or escape velocity than any vehicle in history, apart from the Saturn V moon rocket, which was decommissioned after the Apollo program. This opens a new world of capability for both government and commercial space missions.”[8]

SpaceX originally announced that the Falcon Heavy demonstration rocket would arrive at its west-coast launch location, Vandenberg AFB, California, before the end of 2012,[9] with a launch planned for 2013.[10] After early launches from Vandenberg, the first launch from the Cape Canaveral east coast launch complex was planned for late 2013 or 2014.[8] By late 2012, the company modified the planned first launch date to 2013.[11] Originally, the first launch from the east-coast Cape Canaveral launch complex was planned for 2013, but it is currently scheduled for 2015 with the STP-2 US Air Force payload.[12]

While the initial specifications of the new launcher in April 2011 projected LEO payloads of up to 53,000 kilograms (117,000 lb)[13] and GTO payloads up to 12,000 kilograms (26,000 lb),[14] later reports in 2011 projected higher payloads beyond low Earth orbit, including 19,000 kilograms (42,000 lb) to geostationary transfer orbit,[15] 16,000 kilograms (35,000 lb) to translunar trajectory, and 14,000 kilograms (31,000 lb) on a trans-Martian orbit to Mars.[9][16]

By late 2013, SpaceX had raised the projected GTO payload for Falcon Heavy to up to 21,200 kilograms (46,700 lb).[17]

The Falcon Heavy falls into the "super heavy-lift" range of launch systems under the classification system used by a NASA human spaceflight review panel.[18] SpaceX states that the Falcon Heavy will be able to deliver more usable payload to orbit than any launch vehicle since the Saturn V (1967-1973);[5] the Soviet Energia rocket (which launched twice between 1987 and 1988) could potentially deliver more payload to orbit than the Falcon Heavy when launched without the Buran space shuttle, but Energia was never successfully flown in this capacity (though Energia functioned, the payload failed to complete orbital insertion).[19]

Design

From left to right, Falcon 1, Falcon 9 v1.0, three versions of Falcon 9 v1.1, and two versions of the Falcon Heavy

The Falcon Heavy configuration consists of a standard Falcon 9 with two additional Falcon 9 first stages acting as liquid strap-on boosters,[6] which is conceptually similar to EELV Delta IV Heavy launcher and proposals for the Atlas V HLV and Russian Angara. Falcon Heavy will be more capable than any other operational rocket, with a payload to low earth orbit of 53,000 kilograms (117,000 lb).[10] The rocket was designed to meet or exceed all current requirements of human rating. The structural safety margins are 40% above flight loads, higher than the 25% margins of other rockets.[20]

The Falcon Heavy's designed payload capacity, capabilities, and total thrust are equivalent to the Saturn C-3 launch vehicle concept (1960) for the Earth Orbit Rendezvous approach to an American lunar landing.[21]

First stage

The first stage is powered by three Falcon 9 derived cores, each equipped with 9 Merlin 1D engines.
The Merlin 1D is an updated version of the previous Merlin 1C engine and provides a sea level thrust of 620 kN (140,000 lbf) at a specific impulse of 282 seconds,[22] a vacuum thrust of 690 kN (155,000 lbf) at 311 seconds,[22] and is throttleable from 100% to 70%.[23]

The Falcon Heavy has a total sea-level thrust at liftoff of 17,615 kN (3,960,000 lbf), from the 27 Merlin 1D engines, while thrust rises to 20,000 kilonewtons (4,500,000 lbf) as the craft climbs out of the atmosphere.[5] Falcon Heavy has been designed with a unique propellant crossfeed capability, where some of the center core engines are supplied with fuel and oxidizer from the two side cores, up until the side cores are near empty and ready for the first separation event.[24] This allows engines from all three cores to ignite at launch and operate at full thrust until booster depletion, while still leaving the central core with most of its propellant at booster separation.[25]

After the side cores are released, the center engine in each side core will continue to burn for a few seconds in order to control the trajectory of the side booster.[26][27]

All three cores of the Falcon Heavy arrange the engines in a structural form SpaceX calls Octaweb, aimed at streamlining the manufacturing process,[28] and each core will include four extensible landing legs,[27] which are intended to be used for vertical-landing once the post-mission technology development effort is completed.[29]

Second stage

The upper stage is powered by a single Merlin 1D engine modified for vacuum operation, with an expansion ratio of 117:1 and a nominal burn time of 345 seconds. For added reliability of restart, the engine has dual redundant pyrophoric igniters (TEA-TEB).[6]

The interstage, which connects the upper and lower stage for Falcon 9, is a carbon fiber aluminum core composite structure. Stage separation occurs via reusable separation collets and a pneumatic pusher system. The Falcon 9 tank walls and domes are made from aluminum lithium alloy. SpaceX uses an all-friction stir welded tank. The second stage tank of Falcon 9 is simply a shorter version of the first stage tank and uses most of the same tooling, material and manufacturing techniques. This approach reduces manufacturing costs during vehicle production.[6]

Reusable technology development

Although not a part of the initial Falcon Heavy design, SpaceX is doing parallel development on a reusable rocket launching system that is intended to be extensible to the Falcon Heavy, first to the booster stage and ultimately to the second stage as well.
Early on, SpaceX had expressed hopes that both rocket stages would eventually be reusable.[30] More recently, in 2011, SpaceX announced a funded development program to build and fly a reusable launch system that will ultimately bring a first stage back to the launch site in minutes — and a second stage back to the launch pad, following orbital realignment with the launch site and atmospheric reentry, in up to 24 hours — with both stages designed to be available for reuse within "single-digit hours" after return.[31] As of February 2012, design is complete on the system for "bringing the rocket back to launchpad using only thrusters."[31]

The reusable launch system technology is under consideration for both the Falcon 9 and the Falcon Heavy. It is particularly well suited to the Falcon Heavy where the two outer cores separate from the rocket much earlier in the flight profile, and are therefore both moving at a slower velocity at the initial separation event.[31]

As of March 2013, the publicly announced aspects of the SpaceX reusable rocket technology development effort include an active test campaign of the low-altitude, low-speed Grasshopper vertical takeoff, vertical landing (VTVL) technology demonstrator rocket,[32][33] and a high-altitude, high-speed Falcon 9 post-mission booster-return test campaign where—beginning in late-2013, with the sixth overall flight of Falcon 9—every Falcon 9 first stage which was instrumented and equipped as a controlled descent test vehicle to accomplish propulsive-return over-water tests.[29]

SpaceX has indicated that the Falcon Heavy payload performance to geosynchronous transfer orbit (GTO) will be reduced by addition of the reusable technology, but would fly at much lower launch price. With full reusability on all three booster cores, GTO payload will be 7,000 kg (15,000 lb). If only the two outside cores fly as reusable cores while the center core is expendable, GTO payload would be approximately 14,000 kg (31,000 lb).[34] "Falcon 9 will do satellites up to roughly 3.5 tonnes, with full reusability of the boost stage, and Falcon Heavy will do satellites up to 7 tonnes with full reusability of the all three boost stages," [Musk] said, referring to the three Falcon 9 booster cores that will comprise the Falcon Heavy's first stage. He also said Falcon Heavy could double its payload performance to GTO "if, for example, we went expendable on the center core."

Pricing and development funding

At an appearance in May 2004 before the U.S. Senate Committee on Commerce, Science and Transportation, Elon Musk testified, "Long term plans call for development of a heavy lift product and even a super-heavy, if there is customer demand. We expect that each size increase would result in a meaningful decrease in cost per pound to orbit. ... Ultimately, I believe $500 per pound or less is very achievable."[35] This $500 per pound goal stated by Musk in 2011 is 35 percent of the cost of the lowest-cost-per-pound LEO-capable launch system in a circa-2000 study, referenced by spaceref.com in 2001, the Zenit, a medium-lift launch vehicle that can carry 14,000 kilograms (30,000 lb) into LEO.[36]

As of March 2013, Falcon Heavy launch prices are below $1,000 per pound ($2,200/kg) to low-Earth orbit when the launch vehicle is transporting its maximum delivered cargo weight.[37] The published prices for Falcon Heavy launches have moved some from year to year, with announced prices for the various versions of Falcon Heavy priced at US$80-125 million in 2011,[13] US$83-128 million in 2012,[14] US$77.1-135 million in 2013,[38] and US$85 million for up to 6,400 kg to GTO (with no published price for heavier GTO or any LEO payload) in 2014.[39] Launch contracts typically reflect launch prices at the time the contract is signed.

SpaceX has claimed the cost of reaching low Earth orbit can be as low as US$1,000/lb if an annual rate of four launches can be sustained, and as of 2011 planned to eventually launch 10 Falcon Heavy and 10 Falcon 9 annually.[9] A third launch site, intended exclusively for SpaceX private use, is planned at a site near Brownsville, Texas. SpaceX expects to start construction on the third Falcon Heavy launch facility, after final site selection, no earlier than 2014, with the first launches from the facility no earlier than 2016.[40] In late 2013, SpaceX had projected Falcon Heavy's inaugural flight to be sometime in 2014,[5] but as of March 2014 expects the first launch to be in 2015[41] due to limited manufacturing capacity and the need to deliver on the Falcon 9 launch manifest.[7]

The Falcon Heavy is being developed with private capital. No government financing is being provided for its development.[42]

SpaceX current prices for space launch are already the lowest in the industry.[43] If SpaceX is able to successfully complete development on its SpaceX reusable rocket technology and return booster stages to the launch pad for reuse, a new economically-driven Space Age could result.[42][44]

Testing

A new, partially underground test stand is being built at the SpaceX Rocket Development and Test Facility in McGregor, Texas specifically to test the triple cores and twenty seven rocket engines of the Falcon Heavy.[45]

Launches and potential payloads

Flight Number Date & Time (GMT) Payload Customer Outcome Remarks
1 2015[46][47] Falcon Heavy Demo Flight 1 SpaceX Scheduled Hardware is expected to arrive at the Kennedy Space Center in 2014[46]
2 2015[46] Falcon Heavy Demo Flight 2 called: STP-2[48]
Payload: GPIM[49][50][51]
DoD Scheduled The mission will support the U.S. Air Force EELV certification process for the Falcon Heavy.[47]
3 2016 ViaSat-2 ViaSat Inc. Scheduled Ka-Band broadband satellite.
4 2017[47] Communications satellite[52] Intelsat[53] Scheduled First commercial mission that was booked specifically for Falcon Heavy.[53] First booked launch to a Geostationary transfer orbit for Falcon Heavy.[52]

First commercial contract: Intelsat

In May 2012, SpaceX announced that Intelsat had signed the first commercial contract for a Falcon Heavy flight. It was not confirmed when the first Intelsat launch would occur, but the agreement will have SpaceX delivering satellites to geosynchronous transfer orbit.[52][53]

First DoD contract: USAF

In December 2012, SpaceX announced its first Falcon Heavy launch contract with the United States Department of Defense (DoD). "The United States Air Force Space and Missile Systems Center awarded SpaceX two Evolved Expendable Launch Vehicle (EELV)-class missions" including the Space Test Program 2 (STP-2) mission for Falcon Heavy, initially scheduled to be launched in 2016.[54][48][55]

The Green Propellant Infusion Mission (GPIM) will be a STP-2 payload; it is a technology demonstrator project partly developed by the US Air Force.[49][56]

Proposed missions

In 2011, NASA Ames Research Center proposed a Mars mission "Red Dragon" that would use Falcon Heavy as the launch vehicle and trans-Martian injection vehicle, and the Dragon capsule to enter the Martian atmosphere. The proposed science objectives were to detect "molecules that are proof of life, like DNA or perchlorate reductase" and to drill 3.3 feet (1.0 m) or so underground, in an effort to sample reservoirs of water ice known to lurk under the red dirt." The mission cost as of 2011 was projected to be less than US$425,000,000, not including the launch cost.[57] The concept was to be formally proposed in 2012/2013 as a NASA Discovery mission but has not been selected for funding.[58]

Operator (computer programming)

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Operator_(computer_programmin...