by Craig Nelson
At 11:15 and 11:25, the rod was inched out again. Each time, Fermi showed his viewers where the instruments would fall, and each time he was correct. The controlled and deliberate experiments he had been known for all his life could not be more apparent than now. Everything was being double-checked. At any moment, the pile would self-sustain.
At 11:35, the automatic, solenoid-controlled ZIP rod was removed. The ratcheting of the counters sounded like a motor come to life. The team watched the graph paper’s spot where Fermi had said critical would be recorded.
Suddenly there was a crash, and the entire team fell into shock. Then, all at once, they realized that the automatic rod had fallen into place. The solenoid’s activation threshold had been set too low. After that problem was fixed, Fermi said, “I’m hungry. Let’s go to lunch.”
While eating, the team and their visitors discussed everything but the experiment.
At 2:00, they reassembled, and at 2:20, Fermi had Weil move the control rod back to its previous spot. The instruments were rechecked.
Thirty minutes later, the control rod was pulled another foot, and the counters ratcheted up into a chatter. The pen was thrown off its chart. But this turned out to be another false alarm; like the automatic rod, the pen’s ratios needed to be reset to accurately indicate fission.
Herb Anderson: “At first you could hear the sounds of the neutron counter, clickety-clack, clickety-clack. Then the clicks came more and more rapidly, and after a while they began to merge into a roar; the counter couldn’t follow anymore. That was the moment to switch to the chart recorder. But when the switch was made, everyone watched in the sudden silence the mounting deflection of the recorder’s pen. It was an awesome silence. Everyone realized the significance of that switch; we were in the high-intensity region and the counters were unable to cope with the situation anymore. Again and again, the scale of the recorder had to be changed to accommodate the neutron intensity, which was increasing more and more rapidly.”
At 3:20, George Weil at Fermi’s instruction moved the rod another six inches, and five minutes later, Fermi asked for another foot, and it happened: Weil withdrew the rod.
Turning to Compton, his boss, Enrico explained, “This is going to do it. Now it will become self-sustaining. The trace will climb and continue to climb. It will not level off.”
But as he worked his six-inch ivory slide rule, Fermi’s expression seemed to turn grim. He waited a minute, then reran his rule, looking at some numbers he’d jotted earlier on its back side. A few minutes later he looked over the instruments and ran the calculations again. By now, the individual clicks of the counters could not be heard; there was just an insistent buzz, of neutrons attacking nuclei.
Weil: “I couldn’t see the instruments [so] I had to watch Fermi every second, waiting for orders. His face was motionless. His eyes darted from one dial to another. His expression was so calm it was hard to read. But suddenly, his whole face broke into a broad smile.”
Fermi closed his slide rule and announced with a pleased thrill in his tone, “The reaction is self-sustaining. The curve is exponential.”
For four and a half minutes, the group watched the first nuclear chain reactor producing half a watt of power, their eyes focused on the graph pen, which swept upward and never leveled off. Grad student Leona Woods asked Fermi, in the tone of confirming an instrument’s readout, “When do we become scared?”
Fermi then turned to Zinn: “Okay, ZIP in.” The counters slowed to a fizzle, and the pen stopped its frantic wavering. At 3:53 p.m., it was over. Fermi and Szilard had succeeded in splitting atomic nuclei to produce an immense force. Chicago Pile-1 was the beginning of nuclear medicine, of atomic power and propulsion, and of course the critical start of the Manhattan Project. The Atomic Age was born.
Physicist James Mahaffey: “Fermi’s demonstration of controlled, sustained chain-reacting fission in uranium is the most strangely flawless experiment on record. It was run with 42 witnesses in attendance, dressed in business suits, who watched the world’s 1st operating nuclear reactor do exactly as it was supposed to do. There was no ambiguous evidence, no competing team in another country, no contradictory data, no fudge numbers, and there was no reason to run it a second time to confirm anything. It was simply perfect.”
Eugene Wigner: “Nothing very spectacular had happened. Nothing had moved and the pile itself had given no sound. Nevertheless, when the rods were pushed back in and the clicking died down, we suddenly experienced a letdown feeling, for all of us understood the language of the counter. Even though we had anticipated the success of the experiment, its accomplishment had a deep impact on us. For some time we had known that we were about to unlock a giant; still, we could not escape an eerie feeling when we knew we had actually done it. We felt as, I presume, everyone feels who has done something that he knows will have very far-reaching consequences which he cannot foresee.”
Emilio Segrè: “Probably for Fermi, however, the real victory in the making of a natural uranium reactor had come a few months earlier when he succeeded in building a lattice with k > 1, which was tantamount to reaching criticality. In October 1942 while I was in Chicago on a laboratory errand, he locked me up in a room alone to read a few reports on his work. After an hour or two he returned and found me rather speechless and with bulging eyes. Of course I knew of the attempts to obtain a chain reaction with natural uranium, but I had no precise idea of how far the work had proceeded, although my own work was dependent on the production of plutonium and hence on a functioning nuclear reactor. The progress reports I read impressed me as though I had seen a critical pile with my own eyes.”
Eugene Wigner brought out a bottle of Chianti, which he’d been hiding behind his back, to honor the Italian’s success. The bottle was quite a sign of confidence; Wigner had bought it before America entered the war and Italian imports were banned. Enrico popped it open and passed out paper cups for everyone to have a sip. There were no toasts. Later, however, everyone would autograph the bottle’s straw casket.
Arthur Compton called James Conant at Harvard on the phone. “The Italian navigator has landed in the New World,” he said, in prearranged code, barely able to conceal his excitement.
“How were the natives?” Conant asked.
“Very friendly.”
Arthur Compton: “One of the things that I shall not forget is the expressions on the faces of some of the men. There was Fermi’s face—one saw in him no sign of elation. The experiment had worked just as he had expected and that was that. But I remember best of all the face of Crawford Greenewalt. His eyes were shining. He had seen a miracle, and a miracle it was indeed. The dawn of a new age. As we walked back across the campus, he talked of his vision: endless supplies of power to turn the wheels of industry, new research techniques that would enrich the life of man, vast new possibilities yet hidden.”
Leo Szilard: “There was a crowd there, and when it dispersed, Enrico Fermi and I remained. I shook hands with Fermi and I said that I thought this day would go down as a black day in the history of mankind. I was quite aware of the dangers. . . . But I was also aware of the fact that something had to be done if the Germans get the bomb before we have it. They had knowledge. They had the people to do it and would have forced us to surrender if we didn’t have bombs also.
“We had no choice, or we thought we had no choice.”
6
The Secret of All Secrets
DURING that autumn of 1938 when Enrico Fermi won his Nobel and exiled his family to America, fellow ragazzo Corbino Emilio Segrè was a visiting professor at Berkeley, who learned through the newspapers about Italy’s new anti-Semitic laws, which meant he was now both a man without a job, and a man without a country. In Palermo the year before, Emilio had done what Enrico had failed to do by discovering technetium, the first of what would be an avalanche of human-engineered additions to the periodic table, with Segrè an essential figure in many of those breakthroughs. The head of Berkeley’s Radiation Lab
oratory, Ernest Orlando Lawrence, gave Emilio a job. But what Segrè called “the Cyclotron Republic” paid him so little that he soon left for the Republic’s competitor, the University of California at Berkeley physics department, even though Lawrence’s work was very, very interesting.
Cyclotrons were a racetrack of vacuum tubes edged with magnets and coils—similar to the cat toy that traps a Ping-Pong ball in a spinner track—which pushed and pulled subatomic particles faster and faster, until they were a bright blue beam. Ernest Lawrence described it to would-be investors as a “proton merry-go-round.” Every lab tool in the Cyclotron Republic, from wrench to ruler, had to be made of rust-resistant silicon bronze, with all other steel items banned, from watches to belt buckles, key chains, tie clips, boot tips, and even buttons, since the machine’s magnets were so powerful they could snatch anything steel with immense greed, potentially damaging the beam window, or the accelerator’s delicate mechanisms, or various graduate students in the way.
Known as Maestro or Boss by his subjects, Lawrence was a South Dakota–bred Norwegian Lutheran who’d financed his college education by selling pans door-to-door. In a commencement address, he borrowed from Pasteur and called laboratories “temples of the future—temples of well-being and happiness.” When his beloved cyclotrons failed, however, as they often did, veins would pop out in his temples and he would bellow, “Oh, sugar!” Besides inventing the proton merry-go-round, he was even better than Marie Curie at getting financed. With money from California banker William Crocker, he built the sixty-inch “Crocker Cracker,” but then Ernest found the golden ticket when he convinced Wall Street tycoon Alfred Lee Loomis to turn away from MIT’s original Rad Lab (which pioneered radar and developed the first worldwide radio navigation system—LRN, Loomis Radio Navigation—the most widely used navigation system until GPS) to finance and create the biggest cyclotron on the planet. It would be named for its state of birth—the calutron—and one of its cyclotroneers would be Frank Oppenheimer.
At this time, though, Lawrence and his Republic were less than successful in getting results out of their big science machines. The Berkeley cyclotron had been creating artificial radiation for at least a year when the Joliot-Curies announced their breakthrough, but no one had looked at the instruments after the machine was fired down, so no one noticed that the cyclotrons were irradiating everything, including, they now discovered, the cyclotroneers’ spare change and tooth fillings. Ernest wasted no time in bandwagoning himself onto the Curies’ discovery, curving his machine’s focus to generate medical radioisotopes, with his brother John developing cyclotron isotope science into a profit center in an annex known for its resident test subjects—not the Rad Lab, but the Rat Lab. Ernest had become by this time so financially well-endowed and so politically powerful that Berkeley’s physics department chairman said that they were less a university with a cyclotron than a cyclotron with a university.
Ernest Orlando Lawrence’s best friend, Julius Robert Oppenheimer, was his polar opposite—wealthy, Jewish, of Riverside Drive and Harvard. The two shared bright blue eyes and frequently double-dated, camping in Yosemite and horseback riding through the Berkeley hills. When Oppenheimer—called Bob by his close friends as a child, and Robert or Oppie as an adult—chalked up a notice for a Spanish Loyalists benefit on the Rad Lab blackboard in 1940, Lawrence erased it, yelling that the laboratory was no place for politics. The incident was noted by Luis Alvarez—who was not Hispanic, but of Irish descent, his name pronounced Louie, and who would in time be best known as one of those theorizing the extinction of dinosaurs from extraterrestrial collision—as the first time he had ever seen the two men fight. They were so close that Lawrence even named his second son Robert, much against the wishes of his wife, Molly—she judged her husband’s best friend as lightweight, callow, and fundamentally lacking in character.
By calculating the collapse of dying stars, Robert Oppenheimer predicted what would become the pulsar, and his interest in particle physics would influence the next generation of American physicists. Like the ragazzi Corbino in Rome, Berkeley physics students and visiting acolytes imitated Robert’s style of speech—he murmured while thinking of what to say—as well as his shambling walk, and his baroque chain-smoking. Friend Haakon Chevalier: “He was tall, nervous and intent, and he moved with an odd gait, a kind of jog, with a great deal of swinging of his limbs, his head always a little to one side, one shoulder higher than the other. But it was the head that was most striking: the halo of wispy black curly hair, the fine, sharp nose, and especially the eyes, surprisingly blue, having a strange depth and intensity, and yet expressive of a candor that was altogether disarming.” “He wanted everything and everyone to be special, and his enthusiasms communicated themselves and made these people feel special,” Frank, Oppenheimer’s younger brother, remembered. “He couldn’t be humdrum. He would even work up those enthusiasms for a brand of cigarettes, even elevating them to something special. His sunsets were always the best.”
Another of Oppie’s closest friends was Isidor Rabi, who enjoyed introducing himself to Germans as an Austrian Jew since he knew Austrian Jews were the most hated (he was in fact from an Orthodox Hungarian-émigré family raised on New York’s Lower East Side). Rabi: “Oppenheimer was Jewish, but wished he wasn’t and pretended he wasn’t. . . . [He] never got to be an integrated personality. . . . I remember once saying to him how I found the Christian religion so puzzling, such combination of blood and gentleness. He said that is what attracted him to it. . . . God knows I’m not the simplest person, but compared to Oppenheimer, I’m very, very simple. . . . In Oppenheimer, the element of earthiness was feeble.” There was also what Hans Bethe noted, that “Robert could make people feel that they were fools,” a point echoed by Emilio Segrè: “Oppenheimer’s prestige and ascendancy were great among his close entourage, but he sometimes appeared amateurish and snobbish to people more remote from him, who were not under the spell of his personality. For all his brilliance and solid merits, he had some great defects, which in part account for the mortal enmity by which he was later unjustly victimized. Very conscious of his intellectual distinction, he was occasionally arrogant and thereby stung scientific colleagues when they were most sensitive; furthermore, he was sometimes devious in his actions. All this bore ugly fruit years later.” Then there was this item in the local paper:
J. Robert Oppenheimer, 30, associate professor of physics at the University of California, took Miss Melba Phillips, research assistant in physics . . . for an automobile ride in the Berkeley Hills at 3 o’clock this morning.
He stopped his machine on Spruce Street at Alta Street and tucked a large robe about his passenger.
“Are you comfortable?” Prof. Oppenheimer asked.
Miss Phillips replied that she was.
“Mind if I get out and walk for a few minutes?” he queried.
Miss Phillips didn’t mind, so the professor climbed from the auto and started to walk.
One hour and 45 minutes later Patrolman C. T. Nevins found the professor’s car and Miss Phillips, still comfortable, dozing in the front seat. He woke her up and asked for an explanation of her early morning nap.
Miss Phillips told her story. Police headquarters was notified that Prof. Oppenheimer was missing and a search was launched.
A short time later the professor was awakened from a sound sleep in his room at the Faculty Club, two miles distant from his auto, and asked to explain.
“I am eccentric,” he said.
In 1921, a young woman by the name of Katherine Chaves was told that she was not long for this earth, that soon she would die. Katherine decided to spend the rest of her days as a wife to Winthrop Page, a Chicago millionaire as old as her father, and live out West on the Page family ranch, which lay in a desert of lavender, mariposa, bluebirds, and deer, between the Pecos River and the Sangre de Cristos Mountains, named for their sunsets, when the peaks’ snowcaps burned a red both corporeal and incandescent, like the sacred yet potable
blood of the Lord. The following year, a pale, neurasthenic Jewish boy with such a serious cough his doctors suspected TB (but not chain-smoking) showed up to stay at Katherine’s Los Piños ranch, and she taught him how to ride a horse through the canyons and across the mesas in every kind of weather. Bob returned to New Mexico with brother Frank, and this time, Katherine Page—whose death would not come for decades, and whose husband would never come West—took them ninety-five hundred feet into the peaks, to a cabin with a fireplace made from clay, surrounded by 154 acres of alpine meadow, fields of clover, and heart-stopping views of the Pecos River and the Sangre de Cristos. “Hot dog!” Robert said. “No, Perro Caliente!” Katherine explained. The two boys convinced their father to rent it, a lease Robert would continue as an adult, until he could buy Perro Caliente for $10,000 in 1947. He and Frank went there every chance they could, living the great guy dream of the American West, riding for thousands of miles all the way to Colorado, living on Vienna sausages, chocolate-covered raisins, cheese, and whiskey. During one stay, Oppie wrote to a friend, “My two great loves are physics and New Mexico. It’s a pity they can’t be combined,” and one trek he took with Katherine was through a volcano crater, the Jemez Caldera, and then through a canyon with a stream, along which cottonwood flourished. The canyon was named for the trees: Los Alamos.
In the spring of 1940, Robert invited Dr. Richard Stewart Harrison and his wife, Kitty, for a vacation at Perro Caliente. At the last minute, the doctor had to regretfully decline, but Kitty went anyway and stayed for two months. At summer’s end, Robert called Dr. Harrison to tell him that his wife was pregnant, and the two men agreed that the right thing to do was for Harrison to divorce Kitty and Robert to marry her. When Robert’s best friend, Bob Serber, heard the news, he was so shocked that he wasn’t sure if Oppenheimer had said he would be marrying Jean Tatlock, the great love of his life for decades, or Kitty. It could’ve been either.