Brotherhood of the Bomb

by Gregg Herken

  * * *

  Although Conant had grudgingly agreed to approve a temporary clearance for Oppenheimer, he had not ceased to worry about project security at Berkeley. In February 1942, Conant summoned John Lansdale, a newly promoted captain in the U.S. Army’s Military Intelligence Service, to OSRD headquarters. A Harvard law graduate, Lansdale before the war had defended the Cleveland Railway Company against personal injury suits resulting from trolley accidents. Since being recalled to active duty, he had been assigned to G-2’s Counter-Intelligence Group in Washington.118

  Conant ordered Lansdale to Berkeley in civilian clothes to test security procedures at the Rad Lab. Lansdale was given a temporary membership card for the Faculty Club, obtained by Conant from Sproul, and a copy of a recent Stanford commencement speech by Lawrence describing the operation of the cyclotron.119

  By chance, Lansdale encountered a Berkeley professor on the train en route to California who wrote him a letter of introduction to the dean of the law school, Max Radin.120 Max’s brother, Paul, was an anthropology professor on campus and a member of the political discussion group to which Oppenheimer and Chevalier belonged.

  Renting a room at International House, Lansdale bought a notebook on Telegraph Avenue to serve as a diary and on Friday morning, February 20, strolled up Cyclotron Hill—through a pair of open gates posted with “No Visitors” signs, he noted—to the site of the unfinished 184-inch. After spending a leisurely two hours studying blueprints laid out on a bench and talking with the construction superintendent, Lansdale joined Max Radin for lunch at the Faculty Club. Radin pointed out Lawrence, who, he explained, was a frequent traveler to Washington on a government project seeking “an explosion from the sudden expansion of the atom.”

  Later that afternoon, Lansdale returned to the 184-inch and was considering stealing some of the blueprints when he was noticed by Alvarez and asked to leave. During dinner at the Faculty Club, Lansdale brought up the subject of the cyclotron’s possible military use with Cooksey, who warily skirted the subject, speaking instead of the machine’s application to cancer research.121

  Lansdale spent a total of two weeks in Berkeley getting to know many of those he identified in his diary as “Lawrence’s Brain Trust.” At breakfast one day, chemist Joseph Kennedy boasted that since a pound of U-235 contained enough energy to lift all the buildings in San Francisco half a mile into the air, whichever country separated enough uranium to make a bomb would win the war. But Kennedy told Lansdale that he doubted a way could be found to separate that much uranium before the fighting ended.

  Lansdale returned to Washington in early March to brief Conant. (“Oh, dear … oh, dear,” the Harvard president muttered as Lansdale read from his diary.) Conant promptly ordered Lansdale back to Berkeley, this time in his army uniform.

  Asking Cooksey to assemble the boys, Lansdale read them the same diary entries that had so shocked Conant.122 Subsequently upbraided a second time by Conant, Lawrence promised to tighten security measures at the Rad Lab. Lansdale, with Conant’s blessing, left on a similar mission to Compton’s Met Lab in mid-May.

  * * *

  By that spring, the separation of uranium was progressing well enough on the 37-inch, Lawrence wrote Bush, that the OSRD chairman might have to make good on an earlier wager.123 There was now under way a friendly race between the Calutron and Fermi’s atomic pile as to which would produce the first material for a bomb.124 On May 23, 1942, Lawrence, determinedly upbeat, wrote to Conant that work was “proceeding somewhat faster than anticipated.” He asked for, and got, another $25,000 to make it to the end of June.125

  Later that day, Ernest met in Washington with Conant and the S-1 section leaders to discuss construction of a pilot plant. An NDRC study had recently concluded that electromagnetic separation seemed the most promising method of enriching uranium; results from both gaseous diffusion and the centrifuge looked to be at least a year away. But Conant worried aloud that separating uranium by all known techniques would cost $500 million—and result in “quite a mess of machinery.”126

  Ernest told the S-1 managers that a full-scale electromagnetic separation plant could be producing 100 grams of U-235 a day within a year. Reluctantly, Conant agreed to continue backing all four “horsemen.” But he recommended to Bush that $12 million be spent on an electromagnetic production plant, to be completed by September 1943.127 When the meeting adjourned that afternoon, Lawrence promptly flew back west with the good news.

  On Tuesday evening, May 26, current flowed to the 184-inch for the first time. A few days later, the first C-shaped vacuum chamber was installed between the pole pieces of the giant magnet.128 Lawrence wrote to Bush in mid-June that the results justified a decision for a full-scale factory.129 Ernest wanted both the Calutron pilot plant and the scaled-up production facility to remain on the West Coast, under his direction. He had located a possible site for the production plant in the far northern corner of the state, near Shasta Dam, and was looking into having the university lease to the army a parcel of land in the hills back of the Rad Lab for the pilot plant.130

  By the time he forwarded his own recommendations to Roosevelt on June 17, Bush agreed with Lawrence on the necessity to proceed promptly on all fronts. But he and Conant had already decided to put the army in charge of building the factories that would separate the uranium for the bomb. The president, too, acted with unusual dispatch, approving Bush’s plan on the same day by scrawling “OK. FDR” in blue pencil at the top of the page.

  * * *

  To keep electromagnetic separation in the race and meet OSRD deadlines, Lawrence and Oppenheimer had begun recruiting young physics graduate students on campus for the S-1 Project. One of Oppie’s earlier acolytes, still in his midtwenties, was shocked upon returning to Berkeley that spring to find a “bunch of kids” doing war work at the Rad Lab.131

  Competition for the jobs was brisk. The position of research physicist paid $150 a month—compared to the $65 a teaching assistant received—and included a draft deferment.

  With the 184-inch already up and running, the greatest need was for theoretical physicists to perform calculations aimed at improving the efficiency of the Calutron. Not surprisingly, the best of the young theorists at Berkeley worked for Oppenheimer. Many shared not only their mentor’s passion for physics but likewise his affinity for progressive causes.132

  One such student was Giovanni Rossi Lomanitz, who arrived in Berkeley from Oklahoma in the late summer of 1940, a month before his nineteenth birthday. Big, extroverted, and cheerful, Lomanitz had been immediately swept up in the radical politics and bohemian culture of the place.133 He attended rallies opposing the deportation of labor leader Harry Bridges and joined the Student Workers Federation on campus. Moving into Barrington Hall, a dormitory on campus that attracted students with similarly left-wing views, Lomanitz met other kindred spirits. From Arthur Rosen, Rossi bought a 1927 Nash, biblically nicknamed “Hepzibaa,” for $25. Rosen’s brother, Alfred, was leader of Berkeley’s Young Communist League.134

  Another physics grad student whom Lomanitz befriended was Joseph Weinberg, a New Yorker from the Lower East Side who came to Berkeley via the University of Wisconsin. Only three years older but far more worldly wise than Lomanitz, Weinberg was a graduate of City College, where he had also been a student activist. Like Rossi’s, Weinberg’s parents were Jews who had emigrated from Poland. Joe arrived on campus in spring 1939 with reportedly only the clothes on his back and a spare pair of shoes in a paper sack. By 1941, he was a teaching assistant in Oppenheimer’s undergraduate physics class.135

  A friend to both men was David Bohm, who had graduated from Penn State in 1939 and shortly thereafter came west to work with Oppenheimer. After a frustrating year spent at Caltech, Bohm had followed Oppie north to Berkeley and, at his mentor’s instigation, joined the youthful group working at the lab.136

  Unlike his fellows, Max Friedman arrived in Berkeley as a young man with means. Friedman had grown up in Los Angeles and gradua
ted from UCLA. He drove a shiny new 1942 Pontiac dubbed “Lady Godiva,” one of the last made before the war shut down the production line. Despite his relative affluence, Friedman shared the political views of his peers. He subscribed to the Daily Worker and for a time was Lomanitz’s roommate at Barrington Hall. Like the other three, Friedman was a TA in the physics department when he was recruited to the Rab Lab by Oppenheimer in early 1942.137

  Brought together by their common interest in physics and politics, the foursome—Lomanitz, Weinberg, Bohm, and Friedman—taught classes during the day and attended rallies and protest meetings on weekends. Like many on campus, they and their friends were active in organizations like the Young Communist League, the Campus Committee to Fight Conscription, and the Committee for Peace Mobilization, all branded communist fronts by the Tenney Committee and FBI.138

  The four were also neighbors. By spring 1942, Bohm and Lomanitz had moved into a duplex in a working-class neighborhood just south of campus. Joe and Merle Weinberg rented a one-bedroom apartment on Blake Street, just around the corner. Joined by Friedman, the group gathered often for dinner at the Weinbergs’ home, where they listened to Joe’s coveted collection of classical records and discussed politics and philosophy late into the night.139

  That May, Oppenheimer asked Lomanitz to look over a theoretical paper that two other graduate students, Stanley Frankel and Eldred Nelson, had written on how to improve the focusing of the Calutron beam.140 While uranium was never specifically mentioned, the purpose of the “experiment” was clear.141 Offered full-time employment at the lab by Oppie, Lomanitz understood all too well where such work was headed and balked. Subsequently invited to his mentor’s home on Eagle Hill, Rossi admitted to having ethical qualms about participating in the creation of such a terrible weapon. But Lomanitz, like his professor, had also begun to feel guilty about sitting out the war. He was thinking about quitting school and going to work in the East Bay shipyards or even enlisting, Rossi told Oppenheimer.142

  Two days later, running into Oppie on campus, Lomanitz accepted his offer. As he had done with his brother, Frank, Oppenheimer made Lomanitz and all those working on the project pledge to give up political activity. Oppie had evidently decided against recruiting Weinberg because of Joe’s previous reputation as a campus radical.143

  By that summer, three of the four—Lomanitz, Bohm, and Friedman—were engaged in some form of classified work related to the bomb. Oppenheimer assigned Lomanitz to refining calculations dealing with the Calutron’s magnetic field. Bohm and Friedman supported the efforts of Eldred Nelson and Frankel to better focus the beam. Despite Lawrence’s promise to Conant, the urgent need for results had pushed concerns with security into the background. All three were given interim clearances, pending a more complete background investigation. Until they could be put on the government payroll, Lawrence agreed to pay the salary for Oppie’s students out of the Loomis fund.

  Rossi used his sudden windfall to purchase two blue suits, a phonograph, and a collection of jazz and classical records that he hoped would one day rival Weinberg’s. With gas rationing in effect, Lomanitz used the last of the money to buy a bicycle to commute to his new job at the lab.

  4

  AN ADVENTUROUS TIME

  BY SUMMER 1942, Oppenheimer had become all but indispensable to building the atomic bomb, even as OSRD officials dithered about whether to grant him a security clearance. In May, Gregory Breit had suddenly quit the project—citing, ironically, lax security as the reason in his letter to Bush.1 Arthur Compton promptly assigned Oppie the task of calculating fast-neutron reactions, crucial to the design of the weapon.

  By mid-June, Oppenheimer was at Chicago’s Met Lab to be briefed on the work inherited from Breit. Even Berkeley’s wunderkind found the job and its deadlines daunting. Oppenheimer decided on the spot to invite the country’s top theoretical physicists to Berkeley for an impromptu seminar on bomb physics. It was the start of what Oppie would later describe as “an adventurous time.”2

  First to arrive on campus was Robert Serber, a slight, soft-spoken former student of Oppenheimer’s from the University of Illinois. In 1934, Serber had been on his way to a postdoctoral fellowship at Princeton with his wife, Charlotte, when the couple stopped off at Ann Arbor, Michigan, where Oppie was teaching quantum physics during the summer. Quickly falling under the master’s spell, Serber had followed Oppenheimer back to Berkeley instead.3

  Every spring since, Serber and Charlotte had crowded their possessions into a battered Nash roadster and joined the gypsy caravan of young physicists who migrated south to Caltech with their mentor. In Pasadena, they shared a garden apartment with Frank and Jackie Oppenheimer for $25 a month.

  Like Oppie and Frank, Serber, too, married into radical politics: Charlotte was the daughter of Morris Leof, a Russian émigré and prominent Philadelphia physician who supported a variety of progressive causes in the city. Leof headed the local chapter of a medical aid committee for the Spanish Loyalists. Together with Jean Tatlock and Mary Ellen Washburn, Oppie’s former landlady, Charlotte organized a similar chapter in Berkeley. (Robert Serber evidently inherited his wife’s views. Teller claimed to have been shocked by Serber’s summer 1940 description of the war in Europe as “a clash between capitalist interests.”)4

  Having both physics and politics in common, the Serbers soon became close friends of Oppie and Kitty and were frequent summer guests at Perro Caliente.5 Even after Serber left Berkeley for Urbana, Illinois, in 1938, he and Oppenheimer stayed in touch with weekly letters.

  Anticipating the need for additional theorists, Oppie recruited Serber to the bomb project during a walk in a cornfield near the Illinois campus just before Christmas 1941. Arriving in Berkeley the following spring, the Serbers moved into the apartment above the garage at the Oppenheimers’ house on Eagle Hill. Charlotte found a job as a statistician at the Kaiser shipyards in nearby Richmond.6

  Oppenheimer assigned Serber to oversee the work being done by Nelson and Frankel, who had, in turn, enlisted the assistance of Oppie’s grad students. The latest task was to calculate, using data from the M.A.U.D. report, the critical mass and efficiency of an atomic explosion.7 Distrusting Breit’s estimates, Nelson and Frankel decided to do the laborious neutron diffusion calculations from first principles. Oppenheimer worried that their paper would not be ready in time for his seminar.

  From campuses around the country came those whom Oppie called the “luminaries,” including Harvard’s John Van Vleck and University of Indiana physicist Emil Konopinski, then at Chicago’s Met Lab. Physicist Felix Bloch drove up from nearby Stanford.

  The two brightest stars arrived together on a train from the east. Hans Bethe was working at MIT’s radar lab when Oppenheimer’s summons reached him. Believing the atomic bomb an unlikely prospect anytime soon, Bethe had to be persuaded by Van Vleck to attend; Hans brought his wife, Rose, along for a California vacation. Joining them in Chicago, Edward Teller and his wife, Mici, shared a compartment on the streamliner with the Bethes. Since writing his paper with Bethe on ballistics, Teller had left Columbia to go to Chicago and work with Fermi, but he had not yet been given an assignment at the Met Lab.8

  Although Bethe and Teller had first met as graduate students in Germany during the late 1920s, the two did not get to know each other until 1937, when they spent a summer driving through the western United States, camping and discussing physics.9 They discovered they had much in common.

  Born in Alsace of a Jewish mother, Bethe had been fired from his position at the University of Tübingen in 1933—the victim of Hitler’s racial purity laws—about the same time that Teller was forced from his teaching post at Göttingen’s Institute of Physical Chemistry. Following a brief respite in Copenhagen to study under Bohr, and then England, both men found refuge in professorships at American universities. In 1938, Teller had persuaded Bethe to attend a conference on stellar evolution, a topic on which Bethe would become the world’s expert. Bethe picked Teller as his replac
ement the following summer at Columbia.10

  But in other respects—including temperament—Bethe and Teller were strikingly different. In contrast to Teller’s often gloomy persona, Bethe seemed unfailingly affable and outgoing, with twinkling eyes and a cherubic face.

  Teller had also met Lawrence and Oppenheimer in the vagabond summer of 1937, when he came to Berkeley at Oppie’s invitation to give a seminar. Edward’s lasting memory of Oppenheimer—whose personality he reportedly found “overpowering”—would always be associated with the spicy meal they shared before the seminar at a Mexican restaurant. The hot food caused the guest lecturer to temporarily lose his voice. It was perhaps the only time that Edward would be speechless in Oppie’s presence.11

  Ernest, too, left an indelible impression by taking Teller out on the Bay in his new boat, on a cruise memorable for strong winds and high seas. (“I withstood the choppy waters with a little less than complete equanimity,” Edward later wrote. “Californians seemed to be more than I could handle comfortably.”)

  Arriving in Berkeley in early July 1942, Bethe and Teller looked forward to a pleasant interlude and a welcome break from the war. The two families shared with Konopinski a large house overlooking the Bay on the north side of campus. Teller found it amusing that Konopinski—a big, burly man—wound up with the frilly pink bedroom that had formerly been occupied by the landlord’s daughter. “We have rented, with the Bethes, a palace and enjoy life very greatly,” Teller wrote to Fermi at Chicago.12

  * * *

  The Berkeley seminar began at the start of the second week of July in a seminar room adjacent to Oppie’s office at LeConte. The site had been made secure for the purpose by stretching wire netting over the balcony and posting a campus policeman downstairs. Serber began the first session by describing the current state of knowledge regarding the atomic bomb—how it might work and what it would look like. Oppenheimer relieved the tension that evening by taking his guests to dinner at Spengers, a seafood restaurant near the train tracks in Berkeley.13