Richard P. Feynman, born in Queens on May 11, 1918, was the most extraordinary physicist since Einstein. He was also, briefly and late in life, the most famous scientist in America, the one everybody saw on the news performing a public demonstration of crystalline logic that helped explain a national tragedy.
“Performing” is a loaded word here, for Feynman was a showman, a master teacher who was chosen at the age of 26 to lecture his assembled Manhattan Project colleagues about the theoretical and practical fundamentals of putting together an atomic bomb; who clarified the preposterous impossibilities of quantum electrodynamics (QED) so that laymen might have a chance of appreciating, if not necessarily understanding, the basic laws of physics, chemistry, and biology; and who showed how a piece of rubber plunged into a glass of ice water could reveal the reason the space shuttle Challenger exploded in midair.
Quantum electrodynamics describes the interaction of electrons with light, and it was Feynman’s signature theory. He laid the groundwork for it as a Princeton graduate student and elaborated it as a Cornell assistant professor in 1947-48; he shared the 1965 Nobel Prize in physics for this work, with Julian Schwinger and Shin’ichiro Tomonaga, who independently of one another worked out different versions of the theory. Judged by the standards of classical physics—or the standards of common sense—QED seems absurd, as Feynman enjoyed telling baffled audiences. Electrons behave at once like particles and like waves; positrons, the antimatter counterparts to electrons, can be conceived as electrons traveling backward in time; light does not travel from one point to another in a single straight line but rather pursues every possible path along the way.
And yet the experiments prove the outlandish theory correct. Feynman called it the most reliable and comprehensive theory there is, whose truths paradoxically certify the very laws of classical physics they plainly upend. He was entitled to brag a little:
Out of quantum electrodynamics come all known electrical, mechanical, and chemical laws: the laws for the collision of billiard balls, the motions of wires in magnetic fields, the specific heat of carbon monoxide, the color of neon signs, the density of salt, and the reactions of hydrogen and oxygen to make water are all consequences of this one law.
Feynman’s QED was a dazzling alternative to the forbidding mathematical tangle of Julian Schwinger’s theory, and Feynman made his version all the more attractive with the invention of the Feynman diagrams: On space-time coordinates, line segments represent the motions of electrons and positrons, wiggly lines stand for photons of light being emitted or absorbed, and loops denote some of their more arcane interactions. Although the diagrams can get exceedingly complicated, they proved not nearly as daunting as Schwinger’s algebra; they became a standard instrument in most every physicist’s repertoire, and for a host of uses besides QED.
Feynman was renowned for his unrelenting energy, which he turned to one question after another. Admirers who know about such things tend to agree that he did Nobel-worthy work on the frictionless superfluidity of liquid helium at the temperature of absolute zero, the weak interaction in radioactive decay, and the strong interaction that holds the atomic nucleus together. With less success he also investigated the effect of wind on ocean waves, explored turbulence in gases and liquids, and hauled away at quantum gravitation, which had stymied Einstein. It frustrated Feynman as well—but failure was another way of learning something essential.
Feynman left Cornell for Caltech around 1951 and spent the rest of his career there. He loved his work and he loved his life. Physics was glorious play for him, as he declared repeatedly, and trying to make some sense of the physical world was his inborn response to what he called the wonder and miracle of Nature. Not that he ever gave a serious thought to Nature’s God: He had no need of that hypothesis. He avoided the metaphysical or religious question of why things are as they are, which science at any rate cannot answer; describing how things work would have to suffice. In that sphere he was peerless in his day, acclaimed by his colleagues for his preternatural intuitive grasp of problems that merely formidable minds sweated and groaned over to no avail. Some of his lectures for undergraduates were collected and published in 1964; they have sold more than 1.5 million copies in English and are still widely read.
A crackerjack storyteller, Feynman—who never lost his New York accent—collected autobiographical anecdotes in “Surely You’re Joking, Mr. Feynman!” and “What Do You Care What Other People Think?” The charming stories in these books of his, and in such books about him as James Gleick’s 1992 biography, Genius, depict his vivid, loopy, sometimes brash, and largely alluring personality; his finding diversion in recreational drugs, bongo drums, topless bars, and other amusements not commonly associated with topflight physicists; and his sometimes complicated love life.
When Feynman was asked to serve on the government commission of inquiry into the Challenger disaster in 1986, he was suffering from two rare forms of cancer that would kill him two years later. He proved invaluable to the commission’s work. His famous experiment demonstrated that the rubber O-rings in the rocket booster failed to expand as necessary at an air temperature just below freezing, allowing hot gas to escape from within and precipitate the space shuttle’s explosion. Moreover, he demonstrated the moral courage the other commissioners lacked, calling out NASA managers for their failure to heed the warnings of their engineers and identifying the design problem that built failure into the shuttle system. “Nature cannot be fooled,” he closed his jeremiad on NASA’s follies. The only authority Richard Feynman recognized was the truth, and his devotion to that inviolable standard honored him and the scientific calling.
ALGIS VALIUNAS is a fellow at the Ethics and Public Policy Center and a contributing editor at the New Atlantis, where he writes about scientists’ lives.