The Age of Radiance (20 page)

When Otto Hahn published his results on January 28, Frisch-Meitner was barely mentioned as a footnote. On February 5, 1939, Meitner wrote,
“Your results present a wonderful close chain of results, and it is marvelous what you accomplished in these few short weeks. Unfortunately I fear from the manner in which you brought up our note that you are personally angered by the lapse in our literature citations. I really am terribly sorry. I had hoped a little that our note would’ve given you some pleasure also, and it would’ve been so nice for me if you’d just written that we—independently of your wonderful findings—had come upon the necessity. . . .” The next day she wrote her brother Walter: “Unfortunately I did everything wrong. And I have no self-confidence, and when I once thought I did things well, now I don’t trust myself. The Swedes are so superficial; I don’t fit in here at all, and although I try not to show it, my inner insecurity is painful and prevents me from thinking calmly. . . . And much as [the Hahn-Strassmann discoveries] make me happy for Hahn, both personally and scientifically, many people here must think I contributed absolutely nothing to it—and I’m so discouraged; although I believe I used to do good work, now I’ve lost my self-confidence.”

On February 7, 1939, Hahn apologized to Lise, but then in the end said, “The uranium work is for me a heaven-sent gift.” The explanation for what he had uncovered was actually a Meitner-sent gift, but the erasing of her from history had begun. Because he felt politically weak and his position
tenuous as he wasn’t an ardent Nazi, Hahn wanted to have sole credit for fission, and he started a campaign to get it. The chemist Hahn so misunderstood the physicist Meitner that he thought his observation of barium trumped Meitner’s theory and became enraged when nuclear scientists commonly attributed Meitner-Frisch as scientifically revolutionary . . . and Hahn-Strassmann as mere supporting chemistry. By war’s end, Hahn was claiming that fission could only have been discovered with Meitner away from Dahlem, and today, at Munich’s Deutsches Museum, the collection of Meitner’s instruments and lab equipment is labeled “Worktable of Otto Hahn”—though, in 1983, the museum added a small card of text, mentioning Lise as Otto’s assistant. Biographer Ruth Lewin Sime: “Had fission been born into a world at peace, its energy might first have been used to provide light and heat for people’s homes. Had fission been discovered in a world free of racial persecution, it might well have been the crowning achievement of Lise Meitner’s career.”

When
Nature
finally published the Meitner/Frisch paper on February 11, Irène Joliot-Curie raged at her husband, “We’ve been such dumb assholes
!” Bohr immediately went to Columbia to see Fermi. Herb Anderson:
“Fermi wasn’t in his office at Columbia, so Bohr went down to the basement where the cyclotron was. Fermi wasn’t there, either, but I was. Undeterred, he came right over and grabbed me by the shoulder. Bohr doesn’t lecture to you, he whispers in your ear. ‘Young man,’ he said, ‘let me explain to you about something new and exciting in physics.’ Then he told me about the splitting of the uranium nucleus and how naturally this fit in with the idea of the liquid drop. I was quite enchanted. Here was the great man himself, impressive in his bulk, sharing his excitement with me as if it was of the upmost importance for me to know what he had to say. . . . As soon as he left I rushed off to find Fermi. I found him in his office, but he had anticipated me. He already heard about the fission of uranium from Willis Lamb, who had just heard Bohr talk about it at Princeton. Before I had a chance to say anything he smiled in a friendly fashion and said, ‘I think I know what you want to tell me. Let me explain to you about fission.’ Then he went to the blackboard in his inimitable graphic way to show how the uranium nucleus will split in two. I have to say that Fermi’s explanation was even more dramatic than Bohr’s. It made the experimental possibilities even more exciting. . . . So he says, ‘Why don’t we get the electrode of your ionization chamber, put some uranium on it, let’s go down to the cyclotron, and let’s see if we can see all this energy release.’ And so we got busy just that afternoon. But there was a meeting, a theoretical physics meeting in Washington, the next day. And
Fermi was supposed to go to that. And so he left and I began to wonder what to do and I remembered that Dunning was in and I came to Dunning, and I said, ‘Why don’t we see if we can see this fission?’ ”

What Fermi did not mention to Anderson was his deep shame at missing nuclear fission during his epic radioactive study of the periodic table. Emilio Segrè: “One day after the war Fermi and some of his colleagues were studying the architect’s sketches for the future institute for nuclear science at the University of Chicago. The drawing showed a vaguely outlined human figure in bas-relief over the entrance door. When the group began speculating as to the significance of the human figure, Fermi immediately interjected that it was probably
‘a scientist not discovering fission.’ ” Physicist Jay Orear:
“If Fermi had published that he had seen fission, the half-sized pieces would have an excess of neutrons and these neutrons could give rise to more fissions most likely in a chain reaction. Then both Germany and the United States might have had atom bombs in time for World War II. The world should be grateful for this one mistake by Fermi!”

On the night of January 25, 1939, the first American nuclear fission experiment was conducted in the basement of Columbia’s Pupin Hall. Previously that day, John R. Dunning and Enrico Fermi had lunch at the faculty club and discussed the outlines of future experiments with uranium, such as what would be the best state to test—metal, liquid, or gas? Then Fermi left for the train to Washington, and that night a cold front blew in, rattling Pupin’s scraggly Ivy League vines. At about seven o’clock, Dunning and Herb Anderson bombarded uranium oxide with neutrons in an ionization chamber, fully expecting nothing would happen. However, instead of the whispery dots that would be expected on the oscilloscope, great wavy lines appeared.

John Dunning:
“I went up to the thirteenth floor and brought down one of the old standard stand-by neutron sources, the radon plus beryllium sources that had been used so much before. We put it next to the chamber containing the uranium and in considerable excitement we saw with even this very weak source about one big pulse, a huge pulse, on the oscilloscope every minute. The rate, however, was so slow that I had doubts whether this was really real or whether it was maybe a bad electrical contact. So we had another device, and installing that right next to the chamber, the rate went up according to my notes to something like seven or so with that device, huge pulses. We finally quit about 11 p.m. My notebook contains this phrase: ‘Believe we have observed new phenomenon of far reaching consequences.’ ”

Dunning had never seen anything like it before and took a deep breath.
“God!” he said. “This looks like the real thing.” They assumed that something was wrong and spent the next two hours making sure the machine was working properly, but finally the truth was evident. They had split atoms and released nuclear power, confirming the fission discovered by Meitner and Frisch.

On January 26, the Fifth Annual Conference on Theoretical Physics opened in Washington, DC. Before anyone could present their findings, Bohr and Fermi took the floor of the conference to announce nuclear fission. The audience erupted, with many immediately abandoning the conference to return to their labs and confirm the Meitner and Frisch findings then and there. On January 29, 1939, an excitable
New York Times
explained this moment to the general reader with the headline “Atomic Explosion Frees 200,000,000 Volts,” and on April 29, the head of the physics division of the Reich Research Council, Abraham Esau, assembled a group of German nuclear scientists to form a new organization, the Uranium Club—the Uranverein—and directed them to investigate the potential battlefield uses of fission. At around the same time, the German Army Weapons Bureau started its own rival committee.

When Szilard learned of Meitner and Frisch’s theory of fission, he could only think,
“All the things which H. G. Wells predicted appeared suddenly real to me.” Until Joliot-Curie discovered man-made radiation, no one paid any attention to Szilard’s chain-reaction theories, but the French technique, combined with the Meitner/Frisch findings, now indicated a clear candidate for the trigger that would lead to radioactive power and weaponry, and Szilard’s H. G. Wells–induced epiphany at a London stoplight would become the wellspring of nuclear science. When uranium fissioned, mass was alchemized into energy . . . and a few stray neutrons were spewed. Enrico Fermi:
“It takes one neutron to split one atom of uranium [which then] emits two neutrons. . . . It is conceivable that they might hit two more atoms of uranium, split them, and make them emit two neutrons each. At the end of this second process of fission we would have four neutrons, which would split four atoms. . . . In other words, starting with only a few man-produced neutrons to bombard a certain amount of uranium, we would be able to produce a set of reactions that would continue spontaneously until all uranium atoms were split.” If, as Fermi had found with the paraffin, a tamper could slow the neutrons’ velocity and maximize their strike efficiency, humans could precipitate a controlled chain and extract its energy—a nuclear reactor producing immense amounts of power from small amounts
of ore—as well as isotope by-products for medicine, archaeology, and explosives. If they could trigger an uncontrolled chain reaction releasing massive energy simultaneously, though, it would mean a weapon of unimaginable destructive force.

On February 24, Hungarian Leo Szilard worked with Canadian Walter Zinn at Columbia to determine whether splitting uranium atoms would produce neutrons. At first, their oscilloscope showed nothing whatsoever . . . then they realized they had forgotten to plug it in. Szilard:
“We turned the switch and we saw the flashes. We watched them for a little while and then we switched everything off and went home.”

It was all true; uranium fission produced neutrons.

Leo: “That night, there was very little doubt in my mind that the world was headed for grief.”

E
NRICO FERMI
and Leo Szilard now began a series of experiments together at Columbia to create the first sustained chain reaction—the world’s first nuclear reactor—with various arrangements of neutron sources and uranium to understand the quantity needed, what medium would work best to slow down the neutrons, what kind of uranium worked effectively, what layout of ore and tamper meant the most likely success, and what could be used to stop the reaction, as well as control its speed.

The two fought constantly. Enrico believed in careful, incremental progress and hard work in the lab; Leo loved debate, being a catalyst, and thinking through original ideas at their earliest, most primitive stages. Eugene Wigner believed that Fermi’s most striking trait was
“his willingness to accept facts and men as they were” with an approach to research as shoe-plain as the man himself: “One must take experimental data, collect experimental data, organize experimental data, begin to make a working hypothesis, try to correlate so on, until eventually a pattern springs to life and one has only to pick out the results.” Szilard challenged conventions, upended every authority in every hierarchy, did not mind charging into battle like a scientific Quixote, and tended to operate independently (to put it politely); while Enrico had spent decades leading teams of scientists; he was so enthusiastic about his employees’ efforts and so willing to pitch in at every level that he made it easy to join Team Fermi—and he attracted professional colleagues in droves with his otherworldly mental powers. One said that Enrico had such a feel for neutrons that he could
“predict what would happen in any given experiment to within statistical error, and followed his predictions with detailed calculations and these almost always confirmed his intuitions.”

Szilard, meanwhile, was impulsive and bold, made intuitive leaps, would spew a torrent of possibilities, and was almost too original. Enrico was particularly stunned that Leo didn’t appreciate lab work, seeing one’s theories and calculations rendered manifest in the material world. When Enrico described the experiment that won him a Nobel, the bombarding with neutrons of every element of the periodic table, Leo said that, under a similar situation, he would have hired someone else to do such a “boring task.” Then at Columbia, Leo took one look at the greasy, dust-spewing graphite that he had determined could be used in immense amounts to slow the neutrons for an industrial-strength reactor, as the paraffin had showed them in Rome, and declined to take part, saying he didn’t want to
“work and dirty my hands like a painter’s assistant.” Yet Leo wasn’t shy about showing up in others’ labs to give them unasked-for advice and interrogating scientists about their work and their findings
“with the precision of a prosecuting attorney.” When one afternoon the tactless Szilard barged into Isidor Rabi’s lab, criticizing his techniques, Rabi told Szilard that he should go do his own work and kicked him out:
“You are reinventing the field. You have too many ideas. Please, go away!”