He also took pains to leave his collaboration with Wheeler decisively behind. He wanted his thesis to be his own; he may already have sensed that the absorber theory in itself was leading toward a quirky dead end. It was his conception of the principle of least action that now consumed him. Wheeler-Feynman had been only a starting point, he wrote. It happened to provide most of the “illustrative examples” that would fill out the thesis. But he declared that his least-action method “is in fact independent of that theory, and is complete in itself.”
When he was done, the first part of the thesis looked deceptively old-fashioned. It worked out some nearly textbook equations for the description of mechanical systems, such as springs, coupled together by means of another oscillator. Then this intermediate oscillator disappeared. A stroke of mathematical ingenuity eliminated it. A shorthand calculation appeared, very much like the classical Lagrangian. Soon the ground shifted, and the subject was quantum mechanics. The classical machinery of the first part turned into something quite modern. Where there had been two mechanical systems coupled by an oscillator, now there were two particles interacting through the medium of an oscillating field. The field, too, was now eliminated. A new quantum electrodynamics arose from a blank slate.
Feynman concluded with a blunt catalog of the flaws in his thesis. It was a theory untested by any connection to experiment. (He hoped to find an application to laboratory problems in the future.) The quantum mechanics remained nonrelativistic: a working version would have to take into account the distortions of Newtonian physics that occur near the speed of light. Above all he felt dissatisfied with the physical meaning of his equations. He felt they lacked a clear interpretation. Although few concepts in science seemed more frightening or abstruse than Schrödinger’s wave function, in fact the wave function had achieved a kind of visualizability for physicists, if only as a sort of probabilistic smudge at the edge of consciousness. Feynman acknowledged that his scheme discarded even that fragment of a mental picture. Measurement was a problem: “In the mathematics we must describe the system for all times, and if a measurement is going to be made in the interval of interest, this fact must be put somehow into the equations from the start.” Time was a problem: his approach required, as he said, “speaking of states of the system at times very far from the present.” In the long run this would prove a virtue. For now it seemed to turn the method into a formalism with no ready physical interpretation. For Feynman, an unvisualizable formalism was anathema. The official thesis readers, Wheeler and Wigner, were unperturbed. In June Princeton awarded Feynman his doctoral degree. He attended the ceremony wearing the academic gown that had made him so uncomfortable three years before. He was proud in the presence of his parents. Fleetingly he was annoyed at sharing the platform with honorary-degree recipients; always pragmatic, he thought it was like giving an “honorary electrician’s license” to people who had not done the work. He imagined being offered such an honor and told himself that he would turn it down.
Graduation removed one obstacle to marriage, but only one. According to medical and quasi-medical dogma, tuberculosis was a burden on love. “Should Consumptives Marry?” was the title of a chapter in Dr. Lawrence F. Flick’s 1903 monograph, Consumption a Curable and Preventable Disease. Not without gravely weighing the “risks and burdens,” he warned. And:
The relationship between husband and wife is so intimate that even with great care there may be given opportunity in moments of forgetfulness for conveyance of the disease.
And:
Many a young consumptive mother gets her shroud shortly after she has purchased the christening frock for her babe.
A 1937 Manual of Tuberculosis for Nurses and Public Health Workers declared that marriage should be forbidden:
Marriage is apt to be a very expensive and dangerous luxury to those who are suffering, or have recently suffered, from tuberculosis of the lungs… . If the patient is a woman, she has not only to face the risk of infecting her husband and her children, but she must take into consideration the fact that pregnancy is liable to aggravate existing disease.
As late as 1952 an authoritative text cited Somerset Maugham’s short story “Sanatorium,” about a young couple in love who disregard the customary strictures.
They were both so young and brave that it was a great pity… . One could wish the novelist would rewrite the story with the boy and girl sensibly waiting for several years… . I am addicted to happy endings.
The textbook phrases gave no hint of the howling whirlpool of emotions that came when love and tuberculosis combined. Richard’s parents dreaded his marriage to Arline. Lucille Feynman, especially, found the idea impossible to bear. Her dealings with her son became harsher as she realized how serious his intention was. In the late spring she sent him a cold, handwritten screed bristling with her fear for his health, her fear for his career, her worry about money, and, indirectly, her revulsion at the possibility of sexual relations. She held nothing in reserve.
“Your health is in danger, no I should say your life is in danger,” she wrote. “It is only natural that when you are married you will see more of her.” She worried about what other people would think (an enemy against which Richard and Arline were learning to circle the wagons). Tuberculosis carried a stigma, and the stigma would attach to Richard. “People dread T.B. When you have a wife in a T.B. sanatorium, no one knows it is not a real marriage. & I know the world considers such a man dangerous to associate with.” She told Richard that he was not earning enough money, that he had been loyal enough already, and that Arline “should be satisfied with the status of ‘engagement’ instead of ‘marriage,’ because in such a marriage you are not getting any of the pleasures of marriage, but only the severe burden.” She warned that she and Melville would not help the couple with money under any circumstances. She appealed to his patriotism, saying that the burden of a sick wife would compromise his ability to serve his country. She reminded him that his grandparents had fled European persecution and pogroms for a country whose freedom he took for granted. “Your marriage at this time, seems a selfish thing to do, just to please one person.” She doubted that he sincerely wanted to marry Arline; she asked whether he was not merely trying to please her, “just as you used to occasionally eat spinach to please me.” She said that she loved him and hated to see him make a noble but useless gesture. She said, “I was surprised to learn such a marriage is not unlawful. It ought to be.”
Melville took a calmer tack. He asked Richard to get professional advice at Princeton, and Richard obeyed, consulting his department chairman, Smyth, and the university doctor. Smyth merely said he preferred to keep out of his staff’s private affairs. He kept to that position even when Feynman went to the extreme of pointing out that he would be in contact both with a tubercular wife and with students. The doctor was concerned to make sure that Feynman understood the danger of pregnancy, and Feynman told him they did not intend to make love. (The doctor noted that tuberculosis was an infectious rather than a contagious disease, and Feynman, typically, pressed him on that point. He had a suspicion that the distinction was an artifact of unscientific medical jargon—that, if there was a difference at all, it was a difference of degree only.)
He told his father that he and Arline did not plan to marry any time within the next year. But just a few days later, having received his degree and his new status, he wrote back to his mother, proudly updating his letterhead by penning “Ph.D.” after the printed “Richard Feynman.” He tried to respond reasonably to each argument. Neither Smyth nor the university physician were concerned about any danger to his health, he said. If marriage to Arline would be a burden, it was a burden he coveted. He had realized one day, arranging Arline’s transfer to the sanatorium nearby, that he was actually singing aloud with the sheer pleasure of planning their life together. As far as his duty to country was concerned, he would do whatever was necessary and go wherever he was sent. It was not that he wanted to be noble, he told his mother. N
or was it that he felt obliged to keep a promise he had made years before under different circumstances.
Marrying Arline was distinctly different from spinach. He did not like spinach. Anyway, he said, he had not eaten spinach out of love for his mother. “You misunderstood my motives as a small boy—I didn’t want you angry at me.”
He had made up his mind. He moved into a flat at 44 Washington Road immediately after graduation and for a while did not even tell his mother the address. He rapidly made the final arrangements—as Arline said, “in no time flat”:
I guess maybe it is like rolling off of a log—my heart is filled again & I’m choked with emotions—and love is so good & powerful—it’s worth preserving—I know nothing can separate us—we’ve stood the tests of time and our love is as glorious now as the day it was born—dearest riches have never made people great but love does it every day—we’re not little people—we’re giants … I know we both have a future ahead of us—with a world of happiness—now & forever.
With his parents frightened and unreconciled, he borrowed a station wagon from a Princeton friend, outfitted it with mattresses for the journey, and picked up Arline in Cedarhurst. She walked down her father’s hand-poured concrete driveway wearing a white dress. They crossed New York Harbor on the Staten Island ferry—their honeymoon ship. They married in a city office on Staten Island, in the presence of neither family nor friends, their only witnesses two strangers called in from the next room. Fearful of contagion, Richard did not kiss her on the lips. After the ceremony he helped her slowly down the stairs, and onward they drove to Arline’s new home, a charity hospital in Browns Mills, New Jersey.
LOS ALAMOS
Feynman tinkered with radios again at the century’s big event. Someone passed around dark welding glass for the eyes. Edward Teller put on sun lotion and gloves. The bomb makers were ordered to lie face down, their feet toward ground zero, twenty miles away, where their gadget sat atop a hundred-foot steel tower. The air was dense. On the way down from the hill three busloads of scientists had pulled over to wait while one man went into the bushes to be sick. A moist lightning storm had wracked the New Mexican desert. Feynman, the youngest of the group leaders, now grappled more and more urgently with a complicated ten-dial radio package mounted on an army weapons carrier. The radio was the only link to the observation plane, and it was not working.
He sweated. He turned the dials with nervous fingers. He knew what frequency he needed to find, but he asked again anyway. He had almost missed the bus after having flown back from New York when he received the urgent coded telegram, and he had not had time to learn what all those dials did. In frustration he tried rearranging the antenna. Still nothing—static and silence. Then, suddenly, music, the eerie, sweet sound of a Tchaikovsky waltz floating irrelevantly from the ether. It was a shortwave transmission on a nearby frequency, all the way from San Francisco. The signal gave Feynman a bench mark for his calibrations. He worked the dials again until he thought he had them right. He reset them to the airplane’s wavelength one last time. Still nothing. He decided to trust his calibrations and walk away. Just then a raspy voice broke through the darkness. The radio had been working all along; the airplane had not been transmitting. Now Feynman’s radio announced, “Minus thirty minutes.”
Distant searchlights cut the sky, flashing back and forth between the clouds and the place Feynman knew the tower must be. He tried to see his flashlight through his welder’s glass and decided, to hell with it, the glass was too dim. He looked at the people scattered about Campania Hill, like a movie audience wearing 3-D glasses. A bunch of crazy optimists, he thought. What made them so sure there would be any light to filter? He went to the weapons carrier and sat in the front seat; he decided that the windshield would cut out enough of the dangerous ultraviolet. In the command center twenty-five miles away, Robert Oppenheimer, thin as a specter, wearing his tired hat, leaned against a wooden post and said aloud, “Lord, these affairs are hard on the heart,” as though there had ever been such an affair.
At 5:29:45 A.M., July 16, 1945, just before dawn would have lighted the place called (already) the Jornada del Muerto, Journey of Death, instead came the flash of the atomic bomb. In the next instant Feynman realized that he was looking at a purple blotch on the floor of the weapons carrier. His scientific brain told his civilian brain to look up again. The earth was paper white, and everything on it seemed featureless and two-dimensional. The sky began to fade from silver to yellow to orange, the light bouncing off new-formed clouds in the lee of the shock wave. Something creates clouds! he thought. An experiment was in progress. He saw an unexpected glow from ionized air, the molecules stripped of electrons in the great heat. Around him witnesses were forming memories to last a lifetime. “And then, without a sound, the sun was shining; or so it looked,” Otto Frisch recalled afterward. It was not the kind of light that could be assessed by human sense organs or scientific instruments. I. I. Rabi was not thinking in foot-candles when he wrote, “It blasted; it pounced; it bored its way into you. It was a vision which was seen with more than the eye.” The light rose and fell across the bowl of desert in silence, no sound heard until the expanding shell of shocked air finally arrived one hundred seconds after the detonation.
Then came a crack like a rifle shot, startling a New York Times correspondent at Feynman’s left. “What was that?” the correspondent cried, to the amusement of the physicists who heard him.
“That’s the thing,” Feynman yelled back. He looked like a boy, lanky and grinning, though he was now twenty-seven. A solid thunder echoed in the hills. It was felt as much as heard. The sound made it suddenly more real for Feynman; he registered the physics acoustically. Enrico Fermi, closer to the blast, barely heard it as he tore up a sheet of paper and calculated the explosive pressure by dropping the pieces, one by one, through the sudden wind.
The jubilation, the shouting, the dancing, the triumph of that day have been duly recorded. On the road back, another physicist thought Feynman was going to float through the roof of the bus. The bomb makers rejoiced and got drunk. They celebrated the thing, the device, the gadget. They were smart, can-do fellows. After two years in this brown desert they had converted some matter into energy. The theorists, especially, had now tested an abstract blackboard science against the ultimate. First an idea—now fire. It was alchemy at last, an alchemy that changed metals rarer than gold into elements more baneful than lead.
Accustomed to spending their days in a mostly mental world, the theorists had sweated over messy problems that they could touch and smell. Almost everyone was working in a new field, the theory of explosions, for example, or the theory of matter at extremely high temperatures. The practicality both sobered and thrilled them. The purest mathematicians had to soil their hands. Stanislaw Ulam lamented that until now he had always worked exclusively with symbols. Now he had been driven so low as to use actual numbers, and, even more humbling, they were numbers with decimal points. There was no choosing issues for their elegance or simplicity. These problems chose themselves—ticklish chemicals and exploding pipes. Feynman himself interrupted diffusion calculations to repair typewriters, interrupted typewriter repair to check the safety of accumulating masses of uranium, and invented new kinds of computing systems, part machine and part human, to solve equations that theoretically could not be solved at all. A pragmatic spirit had taken over the mesas of Los Alamos; no wonder the theorists were exhilarated.
Later they remembered having had doubts. Oppenheimer, urbane and self-torturing aficionado of Eastern mysticism, said that as the fireball stretched across three miles of sky (while Feynman was thinking, “Clouds!”) he had thought of a passage from the Bhagavad-Gita, “Now I am become Death, the destroyer of worlds.” The test director, Kenneth Bainbridge, supposedly told him, “We are all sons of bitches now.” Rabi, when the hot clouds dissipated, said he felt “a chill, which was not the morning cold; it was a chill that came to one when one thought, as for instance when I th
ought of my wooden house in Cambridge …” In the actuality of the event, relief and excitement drowned out most such thoughts. Feynman remembered only one man “moping”—his own recruiter to the Manhattan Project, Robert Wilson. Wilson surprised Feynman by saying, “It’s a terrible thing that we made.” For most the second thoughts did not come until later. On the scene the scientists, polyglot and unregulation though they seemed to the military staff, shared a patriotic intensity that faded from later accounts. Three weeks after the test, and three days after Hiroshima—on the day, as it happened, of Nagasaki—Feynman used a typewriter to set down his thoughts in a letter to his mother.
We jumped up and down, we screamed, we ran around slapping each other on the backs, shaking hands, congratulating each other… . Everything was perfect but the aim—the next one would be aimed for Japan not New Mexico… . The fellows working for me all gathered in the hall with open mouths, while I told them. They were all proud as hell of what they had done. Maybe we can end the war soon.