Genius (11 page)
Authors: James Gleick
Feynman had first come on the principle of least action in Far Rockaway, after a bored hour of high-school physics, when his teacher, Abram Bader, took him aside. Bader drew a curve on the blackboard, the roughly parabolic shape a ball would take if someone threw it up to a friend at a second-floor window. If the time for the journey can vary, there are infinitely many such paths, from a high, slow lob to a nearly straight, fast trajectory. But if you know how long the journey took, the ball can have taken only one path. Bader told Feynman to make two familiar calculations of the ball’s energy: its kinetic energy, the energy of its motion, and its potential energy, the energy it possesses by virtue of its presence high in a gravitational field. Like all high-school physics students Feynman was used to adding those energies together. An airplane, accelerating as it dives, or a roller coaster, sliding down the gravity well, trades its potential energy for kinetic energy: as it loses height it gains speed. On the way back up, friction aside, the airplane or roller coaster makes the same conversion in reverse: kinetic energy becomes potential energy again. Either way, the total of kinetic and potential energy never changes. The total energy is conserved.
Bader asked Feynman to consider a less intuitive quantity than the sum of these energies: their difference. Subtracting the potential energy from the kinetic energy was as easy as adding them. It was just a matter of changing signs. But understanding the physical meaning was harder. Far from being conserved, this quantity—the
action
, Bader said—changed constantly. Bader had Feynman calculate it for the ball’s entire flight to the window. And he pointed out what seemed to Feynman a miracle. At any particular moment the action might rise or fall, but when the ball arrived at its destination, the path it had followed would always be the path for which the total action was least. For any other path Feynman might try drawing on the blackboard—a straight line from the ground to the window, a higher-arcing trajectory, or a trajectory that deviated however slightly from the fated path—he would find a greater average difference between kinetic and potential energy.
It is almost impossible for a physicist to talk about the principle of least action without inadvertently imputing some kind of volition to the projectile. The ball seems to
choose
its path. It seems to
know
all the possibilities in advance. The natural philosophers started encountering similar minimum principles throughout science. Lagrange himself offered a program for computing planetary orbits. The behavior of billiard balls crashing against each other seemed to minimize action. So did weights swung on a lever. So, in a different way, did light rays bent by water or glass. Fermat, in plucking his principle of least time from a pristine mathematical landscape, had found the same law of nature.
Where Newton’s methods left scientists with a feeling of comprehension, minimum principles left a sense of mystery. “This is not quite the way one thinks in dynamics,” the physicist David Park has noted. One likes to think that a ball or a planet or a ray of light makes its way instant by instant, not that it follows a preordained path. From the Lagrangian point of view the forces that pull and shape a ball’s arc into a gentle parabola serve a higher law. Maupertuis wrote, “It is not in the little details … that we must look for the supreme Being, but in phenomena whose universality suffers no exception and whose simplicity lays them quite open to our sight.” The universe wills simplicity. Newton’s laws provide the mechanics; the principle of least action ensures grace.
The hard question remained. (In fact, it would remain, disquieting the few physicists who continued to ponder it, until Feynman, having long since overcome his aversion to the principle of least action, found the answer in quantum mechanics.) Park phrased the question simply: How does the ball know which path to choose?
“Let none say that the engineer is an unsociable creature who delights only in formulae and slide rules.” So pleaded the MIT yearbook. Some administrators and students did worry about the socialization of this famously awkward creature. One medicine prescribed by the masters of student life was Tea, compulsory for all freshmen. (“But after they have conquered their initial fears and learned to balance a cup on a saucer while conversing with the wife of a professor, compulsion is no longer necessary.”) Students also refined their conversational skills at Bull Session Dinners and their other social skills at an endless succession of dances: Dormitory Dinner Dances, the Christmas Dance and the Spring Dance, a Monte Carlo Dance featuring a roulette wheel and a Barn Dance offering sleigh rides, dances to attract students from nearby women’s colleges like Radcliffe and Simmons, dances accompanied by the orchestras of Nye Mayhew and Glenn Miller, the traditional yearly Field Day Dance after the equally traditional Glove Fight, and, in the fraternity houses that provided the most desirable student quarters, formal dances that persuaded even Dick Feynman to put on a tuxedo almost every week.
The fraternities at MIT, as elsewhere, strictly segregated students by religion. Jews had a choice of just two, and Feynman joined the one called Phi Beta Delta, on Bay State Road in Boston, in a neighborhood of town houses just across the Charles River from campus. One did not simply “join” a fraternity, however. One enjoyed a wooing process that began the summer before college at local smokers and continued, in Feynman’s case, with insistent offers of transportation and lodging that bordered on kidnapping. Having chosen a fraternity, one instantly underwent a status reversal, from an object of desire to an object of contempt. New pledges endured systematic humiliation. Their fraternity brothers drove Feynman and the other boys to an isolated spot in the Massachusetts countryside, abandoned them beside a frozen lake, and left them to find their way home. They submitted to wrestling matches in mud and allowed themselves to be tied down overnight on the wooden floor of a deserted house—though Feynman, still secretly afraid that he would be found out as a sissy, made a surprising show of resisting his sophomore captors by grabbing at their legs and trying to knock them over. These rites were tests of character, after all, mixed with schoolboy sadism that colleges only gradually learned to restrain. The hazing left many boys with emotional bonds both to their tormentors and to their fellow victims.
Walking into the parlor floor of the Bay State Road chapter house of Phi Beta Delta, a student could linger in the front room with its big bay windows overlooking the street or head directly for the dining room, where Feynman ate most of his meals for four years. The members wore jackets and ties to dinner. They gathered in the anteroom fifteen minutes before and waited for the bell that announced the meal. White-painted pilasters rose toward the high ceilings. A stairway bent gracefully up four flights. Fraternity members often leaned over the carved railing to shout down to those below, gathered around the wooden radio console in one corner or waiting to use the pay telephone on an alcove wall. The telephone provided an upperclassman with one of his many opportunities to harass freshmen: they were obliged to carry nickels for making change. They also carried individual black notebooks for keeping a record of their failures, among other things, to carry nickels. Feynman developed a trick of catching a freshman nickel-less, making a mark in his black book, and then punishing the same freshman all over again a few minutes later. The second and third floors were given over entirely to study rooms, where students worked in twos and threes. Only the top floor was for sleeping, in double-decker bunks crowded together.
Compulsory Tea notwithstanding, some members argued vehemently that other members lacked essential graces, among them the ability to dance and the ability to invite women to accompany them to a dance. For a while this complaint dominated the daily counsel of the thirty-odd members of Phi Beta Delta. A generation later the ease of postwar life made a place for words like “wonk” and “nerd” in the collegiate vocabulary. In more class-bound and less puritanical cultures the concept flowered even earlier. Britain had its boffins, working researchers subject to the derision of intellectual gentlemen. At MIT in the thirties the nerd did not exist; a penholder worn in the shirt pocket represented no particular gaucherie; a boy could not become a figure of fun merely by studying. This was fortunate for Feynman and others like him, socially inept, athletically feeble, miserable in any but a science course, risking laughter every time he pronounced an unfamiliar name, so worried about the other sex that he trembled when he had to take the mail out past girls sitting on the stoop. America’s future scientists and engineers, many of them rising from the working class, valued studiousness without question. How could it be otherwise, in the knots that gathered almost around the clock in fraternity study rooms, filling dappled cardboard notebooks with course notes to be handed down to generations? Even so, Phi Beta Delta perceived a problem. There did seem to be a connection between hard studying and failure to dance. The fraternity made a cooperative project of enlivening the potential dull boys. Attendance at dances became mandatory for everyone in Phi Beta Delta. For those who could not find dates, the older boys arranged dates. In return, stronger students tutored the weak. Dick felt he got a good bargain. Eventually he astonished even the most sociable of his friends by spending long hours at the Raymore-Playmore Ballroom, a huge dance hall near Boston’s Symphony Hall with a mirrored ball rotating from the ceiling.
The best help for his social confidence, however, came from Arline Greenbaum. She was still one of the most beautiful girls he knew, with dimples in her round, ruddy face, and she was becoming a distinct presence in his life, though mostly from a distance. On Saturdays she would visit his family in Far Rockaway and give Joan piano lessons. She was the kind of young woman that people called “talented”—musical and artistic in a well-rounded way. She danced and sang in the Lawrence High School revue, “America on Her Way.” The Feynmans let her paint a parrot on the inside door of the coat closet downstairs. Joan started to think of her as an especially benign older sister. Often after their piano lesson they went for walks or rode their bicycles to the beach.
Arline also made an impression on the fraternity boys when she started visiting on occasional weekends and spared Dick the necessity of finding a date from among the students at the nearby women’s colleges or (to the dismay of his friends) from among the waitresses at the coffee shop he frequented. Maybe there was hope for Dick after all. Still, they wondered whether she would succeed in domesticating him before he found his way to the end of her patience. Over the winter break he had some of his friends home to Far Rockaway. They went to a New Year’s Eve party in the Bronx, taking the long subway-train ride across Brooklyn and north through Manhattan and returning, early in the morning, by the same route. By then Dick had decided that alcohol made him stupid. He avoided it with unusual earnestness. His friends knew that he had drunk no wine or liquor at the party, but all the way home he put on a loud, staggering drunk act, reeling off the subway car doors, swinging from the overhead straps, leaning over the seated passengers, and comically slurring nonsense at them. Arline watched unhappily. She had made up her mind about him, however. Sometime in his junior year he suggested that they become engaged. She agreed. Long afterward he discovered that she considered that to have been not his first but his second proposal of marriage—he had once said (offhandedly, he thought) that he would like her to be his wife.
Her well-bred talents for playing the piano, singing, drawing, and conversing about literature and the arts met in Feynman a bristling negatively charged void. He resented art. Music of all kinds made him edgy and uncomfortable. He felt he had a feeling for rhythm, and he had fallen into a habit of irritating his roommates and study partners with an absentminded drumming of his fingers, a tapping staccato against walls and wastebaskets. But melody and harmony meant nothing to him; they were sand in the mouth. Although psychologists liked to speculate about the evident mental links between the gift for mathematics and the gift for music, Feynman found music almost painful. He was becoming not passively but aggressively uncultured. When people talked about painting or music, he heard nomenclature and pomposity. He rejected the bird’s nest of traditions, stories, and knowledge that cushioned most people, the cultural resting place woven from bits of religion, American history, English literature, Greek myth, Dutch painting, German music. He was starting fresh. Even the gentle, hearth-centered Reform Judaism of his parents left him cold. They had sent him to Sunday school, but he had quit, shocked at the discovery that those stories—Queen Esther, Mordechai, the Temple, the Maccabees, the oil that burned eight nights, the Spanish inquisition, the Jew who sailed with Christopher Columbus, the whole pastel mosaic of holiday legends and morality tales offered to Jewish schoolchildren on Sundays—mixed fiction with fact. Of the books assigned by his high-school teachers he read almost none. His friends mocked him when, forced to read a book, any book, in preparing for the New York State Regents Examination, he chose
Treasure Island
. (But he outscored all of them, even in English, when he wrote an essay on “the importance of science in aviation” and padded his sentences with what he knew to be redundant but authoritative phrases like “eddies, vortices, and whirlpools formed in the atmosphere behind the aircraft …”)
He was what the Russians derided as
nekulturniy
, what Europeans refused to permit in an educated scientist. Europe prepared its scholars to register knowledge more broadly. At one of the fateful moments toward which Feynman’s life was now beginning to speed, he would stand near the Austrian theorist Victor Weisskopf, both men watching as a light flared across the southern New Mexico sky. In that one instant Feynman would see a great ball of flaming orange, churning amid black smoke, while Weisskopf would hear, or think he heard, a Tchaikovsky waltz playing over the radio. That was strangely banal accompaniment for a yellow-orange sphere surrounded by a blue halo—a color that Weisskopf thought he had seen before, on an altarpiece at Colmar painted by the medieval master Matthias Grünewald to depict (the irony was disturbing) the ascension of Christ. No such associations for Feynman. MIT, America’s foremost technical school, was the best and the worst place for him. The institute justified its required English course by reminding students that they might someday have to write a patent application. Some of Feynman’s fraternity friends actually liked French literature, he knew, or actually liked the lowest-common-denominator English course, with its smattering of great books, but to Feynman it was an intrusion and a pain in the neck.
