The First War of Physics (25 page)

By September, Stalingrad was virtually overrun. The city had been firebombed and turned to blackened rubble by the Luftwaffe. Stalin insisted there would be no step backwards, and prevented civilians from leaving the city in order to encourage greater resistance by Soviet forces. The average life expectancy of a Soviet private newly arrived in the city fell to under 24 hours. But there was no surrender. Under the inspired leadership of General Vasily Chuikov, the Soviet 62nd Army defended the ruins of every building and every factory. Every territorial gain the Germans made during the day would be taken back by the Red Army at night. The battle for Stalingrad was fast becoming the bloodiest battle in human history.

Site Y

Within a few weeks of taking up his new assignment in September 1942, Groves embarked on an inspection tour of the facilities engaged in the American atomic bomb programme. What he saw was quite disheartening.

His first stop was Pittsburgh, and the research laboratories of Westinghouse Electric and Manufacturing Company. Work on centrifugal isotope separation had continued at the University of Virginia and at the Standard Oil Development Company’s laboratory at Bayway, New Jersey, where a pilot plant was eventually constructed. Westinghouse was charged
with the task of making the large, high-speed centrifuges needed for full-scale production of U-235. It was not an auspicious place to start the tour. The researchers had encountered major engineering problems and the work did not appear to have high priority. On Groves’ advice, the project was closed down shortly afterwards.

From Pittsburgh, Groves travelled to Columbia University in New York, where work on gaseous diffusion was being conducted under the overall supervision of chemist Harold Urey. While the scientists he met there were more optimistic about this separation method, the corrosive tendencies of uranium hexafluoride were still causing major headaches. A gaseous diffusion plant would require innumerable porous barriers. These barriers had to be made from a material capable of resisting corrosion. No such material had yet been found. Groves thought the work should continue, but was doubtful that anything would come of it.

From Columbia, Groves headed westwards to the Met Lab in Chicago, arriving on 5 October. The work on the experimental reactor supervised by Fermi appeared to be progressing well. However, Groves was struck by the scientists’ lack of clarity on what he understood from an engineering perspective to be quite fundamental parameters. If a bomb was to be built in time, then the programme needed to have answers to certain key questions: How much? How big? How long? The physicists appeared still to be content dealing with orders of magnitude estimates. Groves reminded them that if they were charged with the task of catering for a wedding reception, then being advised to expect anywhere between ten and a thousand guests was not a basis on which any kind of proper planning could be done.

Surrounded as he was by ‘eggheads’, Groves felt it necessary to point out to his audience, which included several Nobel laureates, that he was not overawed by their intellect. His ten years of formal education, he contended, must surely be equivalent to about two Ph.Ds. He left them to ponder the significance of this. Szilard, who had been in the audience, did not need long to ponder. ‘How can you work with people like that?’ he exclaimed later to his colleagues. In Szilard’s case, the feelings were mutual.
Groves identified Szilard as a troublemaker almost immediately, and tried hard to have him locked up for the duration of the war.
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From Chicago, Groves travelled further westwards to the Rad Lab at Berkeley, arriving on 8 October. Lawrence, the accomplished showman, made a very favourable impression. Here in California, Groves thought, he was at last going to get some good news. Lawrence promised him a demonstration of his latest machine. By now Lawrence had graduated from the 37-inch cyclotron to the new 184-inch super-cyclotron which had been completed and was ready for operation in June 1942. The cyclotrons adapted to separate U-235 had been renamed ‘calutrons’ in honour of the University of California.

The 184-inch calutron was housed in a large circular building on Charter Hill, behind the Berkeley campus. Lawrence sat at the controls of this massive machine and explained how it worked. Suitably impressed, Groves asked how long it would take to get a real separation. Lawrence admitted that they hadn’t so far achieved any sizeable separation. The machine had not yet been run for more than ten or fifteen minutes at a time. It needed between fourteen and 24 hours’ operation just to achieve a proper vacuum.

Now seriously depressed, Groves made his way to Oppenheimer’s office in Le Conte Hall. This meeting did not go the way that might have been predicted. Oppenheimer, the underweight, ascetic, radical intellectual capable of brilliance and arrogance in near equal measure, contrasted starkly with the military careerist sitting opposite. Groves was a sweet-toothed, overweight, conservative son of a Presbyterian minister with an engineer’s pragmatism and distaste for intellectualism. Hardly a match made in heaven. Yet the two hit it off almost immediately, principally because Oppenheimer was keen to impress and win Groves over. His work on the atomic bomb project had given him a new sense of direction, and possibly a new lease of scientific life, and he wanted to ensure he at least retained his position.

Groves was struck by Oppenheimer’s obvious capabilities as a physicist, his grasp of the situation and his ability to explain the science intelligibly. Most importantly of all, Groves found Oppenheimer curiously reassuring. ‘There are no experts,’ Oppenheimer claimed, ‘The field is too new.’ Oppenheimer argued that all the scientists working on the principles of bomb physics and design be brought together at a single, dedicated laboratory where they could work to solve the many problems they faced.

Groves had been thinking along the same lines, and had already conceived of the dedicated laboratory as ‘Site Y’. He had gone to Berkeley with the intention of asking Lawrence to head the new laboratory but had concluded that Lawrence was critical to the success of the electromagnetic separation project. Groves swiftly reached a conclusion. He agreed with Oppenheimer that the programme needed a central laboratory, to be run as a military establishment. He also judged that Oppenheimer was best placed to serve as its scientific director, which may have been precisely the conclusion that Oppenheimer was seeking. Groves offered him the position the following week, on 15 October.

To many involved in the project, Oppenheimer’s appointment was ‘improbable’. There were many objections. Oppenheimer was a noted theoretician with a typical theoretician’s clumsiness near experimental apparatus. Although this was a project that demanded theoretical input, it was principally going to be an experimental and engineering project, managed and run on a scale the like of which few physicists had experience of, and of which Oppenheimer had none. ‘He couldn’t run a hamburger stand’, was one fairly typical observation. The project team would no doubt number a good many Nobel laureates, yet Oppenheimer himself had not won a Nobel prize.

And, of course, there were the security issues raised by his former Communist associations. On 10 October an FBI bug in Steve Nelson’s Oakland office had picked up a conversation referring to ‘an important weapon that was being developed’ and an important contact on the project whom the FBI surveillance team believed was Oppenheimer himself.

The objections fell on deaf ears. Groves had found his man and he railroaded the decision through various committees. Oppenheimer was appointed on 19 October 1942.

Attention turned to the search for Site Y, the location of the new central laboratory. A remote wooded canyon in New Mexico, Jemez Springs, was rejected by Oppenheimer as too gloomy and depressing and by Groves because the site lacked existing buildings. Oppenheimer knew this area quite well. It was here that he had recovered from tuberculosis in the summer of 1928, staying at a log cabin on wooded slopes opposite the Sangre de Cristo mountain range. The cabin was nicknamed Perro Caliente (Spanish for ‘hot dog’) and always referred to by Oppenheimer as a ‘ranch’.
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That summer, he and his brother Frank had explored this whole area on horseback.

At Oppenheimer’s suggestion, the search party drove on from Jemez Springs to a mesa on the other side of the Jemez mountains, and a private boy’s school that he remembered from his tours of the area. This was the Los Alamos Ranch School, which had been established in 1917 by a Detroit businessman to provide a healthy, outdoors environment and a classical education for the sickly, coddled children of the well-to-do. It was affiliated to the Boy Scouts (the students at the school belonged to the mounted Los Alamos Troop 22). Alumni of the school included William Burroughs and Gore Vidal. The school was well known to Conant – he had once considered sending his youngest son there.

The site had buildings and supplies of water and electricity but the road up to the mesa from Santa Fe, 30 miles south-east, was little more than a dirt track. Groves nevertheless liked the site’s isolation. At this stage Oppenheimer had estimated that the laboratory would need to house no more than 30 or so scientists, plus supporting personnel. Groves agreed to the location on the spot, and negotiations for the purchase of the site began within a week. The purchase was completed quickly, as the school had never really recovered from the Depression. Its last graduates, which included the grandson of the founder, received their diplomas on 21 January 1943.

Oppenheimer had started unofficially recruiting scientists for the laboratory within days of his appointment. Now that Site Y had been identified, he and Lawrence began recruiting in earnest. Many that they approached were reluctant, however, some citing the remoteness of the location as a reason. Szilard, for one, declared: ‘Nobody could think straight in a place like that. Everybody who goes there will go crazy.’

However, most of the scientists they approached were more concerned about the implications of working at a military laboratory and baulked at the idea of joining the army. Oppenheimer had not given this a second thought – he had happily reported for an army physical examination and had even been measured for a uniform. But he was persuaded by physicists Isidor Rabi and Robert Bacher, who were both busy working on radar at MIT, that the laboratory should retain ‘scientific autonomy’ and that joining the army should not be a prerequisite. Groves reluctantly agreed, provided the military retained authority and responsibility for security at the site.

The scientists working at Los Alamos could retain autonomy and continue as civilians, but at the cost of security measures that would give the laboratory the appearance of a concentration camp.

A game of murders

Despite the Canadian government’s eagerness to embrace the proposal to relocate the Tube Alloys reactor team to Montreal, there remained concern about the number of non-British nationals who were to participate. As the scope of the project expanded, so too did the number of émigré scientists. Among these was George Placzek, already in America, who had agreed to become head of a new theoretical physics division at the Montreal laboratory. When it was suggested that the Italian physicist Bruno Pontecorvo join the project, the Canadians protested. But physicists of Pontecorvo’s calibre (he had been part of Fermi’s nuclear physics group in Rome) were in short supply, and many of those of British nationality were already
accounted for by other projects. It was eventually agreed that Pontecorvo would join the team.

When in January 1943 the small party of scientists left Britain for Canada on a banana boat, Alan Nunn May was the only British-born scientist in the group. May was, like Fuchs, another quiet, withdrawn figure who rarely spoke unless spoken to and seemed to have few friends. He had been educated at Cambridge and, although not overtly politically active, served for a time on the editorial board of the
Scientific Worker
, the journal of the National Association of Scientific Workers, an organisation that had been infiltrated by Communists. He had joined Tube Alloys in April 1942, returning to the Cavendish Laboratory from Bristol, where he had been evacuated in the first months of the war.

Although there is no direct evidence that he was in contact with Soviet intelligence during this time, subsequent events would reveal that he was, in fact, a GRU spy, most probably recruited by one among the Cambridge spy ring.

To pass the time as they crossed the Atlantic, the party organised a few social events and games. One evening they played the game of murders, in which participants follow a series of clues to uncover the murderer among them. When one of the party took their turn to play the detective, she noticed that May stood rather aloof and detached from the proceedings. This was not untypical behaviour, and she quickly put him out of her mind as she turned her attention to the mystery at hand.

But it was May who was the murderer.

Raid on Vemork

Torstein Skinnarland was arrested in one of many German sweeps of the local population following the failed commando raid on Vemork. He was sent with his brother Olav to Grini concentration camp. Einar was forewarned of the raid and managed to escape onto the Hardanger Plateau, where he joined Poulsson and the other members of the advance party.

Einar Skinnarland was a fortunate addition to the team. He was able to procure supplies and his good-natured approach to their hardships helped
keep their spirits up. With his help, the advance party – now renamed Swallow – managed to maintain wireless contact with SOE headquarters in Britain.

Back in London, the SOE was faced with a very difficult decision. Forty-one personnel had perished in the failed Freshman operation. Yet the high concentration cells at Vemork remained intact and continued to supply the heavy water required by the German atomic project. Nothing had changed: the destruction of the heavy water plant remained a top priority, although this was a task now made doubly difficult.

It was obvious that an operation like Freshman could not be repeated. Combined Operations passed the challenge back to the SOE, and an alternative plan was devised. This time, the SOE had the advantage of Brun’s intimate – and recent – knowledge of the plant. Both Tronstad and Brun felt strongly that a small sabotage party could succeed where the larger-scale commando raid had failed.