After Fox’s post-doctoral study, the two friends had corresponded for years, exchanging results of their latest work. They shared the excitement of Dirac’s relativistic field theory, the discovery of spinor mathematics… to them, physics was apolitical, a true bridge between cultures. Did an atomic nucleus care about inequities in the Treaty of Versailles? No matter what governments might squabble about, physics remained immutable. Fox admired that. Esau had always agreed with him.
And now, because of the war, his friendship with Esau had become illegal. Fox wanted to write his old companion, tell him that their communications must stop, but he had reluctantly adhered to the rules. Letters between himself and Esau had dwindled over the past few years, since Germany had declared war on the U.S. after the Pearl Harbor attack. But Fox’s friendship had never stopped, and he knew Esau must feel the same.
A colleague at William and Mary College had agreed to mail Fox’s letters to another colleague in Mexico, where in turn they would be sent to Norway, then forwarded to one of the occupied countries. A letter might take months to cover this circuitous route, but Fox and Esau kept their communication open.
And pointedly nonpolitical.
Fox’s leanings were certainly not toward Germany—but they did not rest blindly with the Allies either. He had heard much talk of a single world government lately. In Fox’s view, any one independent government was as bad as any other, especially if both used their weapons for mass destruction. Look at the horrible poison gas weapons used during the Great War. The great physicist Otto Hahn himself had created those weapons—was that a fitting purpose for such a man to apply his mind?
As a physicist, he believed the world could flourish without political meddling. Governments demanded too much. Physicists knew how to handle relations between countries. After all, new scientific ideas and discoveries had been exchanged freely for years. It seemed that only the bureaucrats, the militarists, and—worst of all—the bean counters, could not accept the laws of Nature for what they were.
No one government should have an upper hand, an ace in the hole it could use to dominate anyone else. It would be like two men standing in a room with loaded pistols aimed at each other. No sane person would pull the trigger, for fear that both might die. But if only one man held a gun, he might be tempted to take a preemptive action. He would feel superior, with nothing to worry about…. How could the U.S. be trusted with a doomsday weapon such as the atomic bomb, when no other country could?
Fox feared the pace the American program was setting. Did the Germans know that Enrico Fermi’s reactor, constructed in secret under the squash court at the University of Chicago, had achieved a self-sustaining nuclear reaction? It had never been done before, and marked a true milestone in the history of physics—but the results had remained a tight secret. Such breakthroughs were not to be kept under lock and key!
Fermi had used a common substance—graphite of all things!—as a moderator to slow the neutrons down in natural uranium, making it possible for them to split the uranium-235 isotope and create more neutrons to keep the reaction going. Some nuclei of the overwhelming majority of uranium-238 absorbed a neutron, thereby transmuting into a new element, one step higher in the periodic table.
Thanks to the efforts of Leo Szilard, and his constant harping for secrecy from the Germans, the news that would ordinarily be reported in Physical Review now was shared among only a few scientists whose political views were considered acceptable. What trash! German scientists like Esau might never know the simple technique, and the warring countries would continue to threaten each other with nearly completed “secret weapons.”
He had been strongly tempted to write Esau then, to tell him of Fermi’s chain reaction. He had sweated for days, changing his mind over and over again, until finally his own fear had won. But the innocuous remark that woman Elizabeth Devane had made set him to thinking again. What if Werner Heisenberg had somehow mucked up the data? What if he had miscalculated cross-sections? It was certainly possible, even for a Nobel Prize winner. Normally the physics and experimental data would be checked and cross-checked at every point when such an important application hinged on the results. But when the most respected of all German physicists, the creator of the quantum Uncertainty relation himself, stood by his results, no one chose to question him in the secrecy of war.
Fox snorted. Elizabeth Devane would have had no way of knowing… yet she had struck him as odd, the carefully prepared and trained person, so cleverly disguised that no one would suspect. Wasn’t that the way spies worked? In an undertaking as huge as the Manhattan Project, Fox thought it unrealistic that the Nazis had planted no informant. And what better cover than as an unobtrusive filing clerk who happened to have a physics background much more extensive than seemed reasonable for a simple woman? Elizabeth could quietly keep track of everything going on at Los Alamos and report back to Berlin at her convenience.
He mused about what she had said. What if Heisenberg was working for the Allies, sabotaging his research to keep Hitler’s work far behind what the others could accomplish? What if Elizabeth’s information went to the wrong people, the true Nazi warmongers, not trusted scientists like Abraham Esau?
The whole idea was preposterous. But yet… how had Elizabeth even imagined such a thing? What did she know?
That image of two men with loaded pistols seemed dangerously stabilizing when compared with a monopoly of power on either side. Equally matched, the two sides would be forced toward peace; given a bigger stick than anyone else in the world, even the most democratic nation would turn into a playground bully.
Fox knew it was dangerous to contact Esau at all, but this new insight was just too important not to pass on. The news of Fermi’s reaction had almost been enough incentive, almost, and Elizabeth’s comment had added the extra bit to tip the scales. He tucked the letter back in his jacket pocket.
The bus jarred Fox as it hit a pothole. The windows rattled and the springs creaked. Santa Fe spread out in front of him in all its historical aplomb. Brown adobe buildings lined the street, splashed with color from bundles of red chili pepper hung by doorways. Colorful Mexican tiles encircled the round-cornered windows. As stark decoration, black wrought-iron gates and bars adorned some of the houses.
A young man stood up at the front of the bus. Although dressed in typical civilian attire of white shirt, baggy gray pants, and a thin dark tie, the man seemed out of place. His mannerisms gave off an invisible signal that said “military,” G-2—not just another Nice Young Man who seemed anxious to help the scientists feel at ease on their R-and-R outing. This was, after all, the American celebration of Independence Day. Independence from Britain—Fox found that ironic. The G-2 man would probably have every person on the bus watched all day. The man cleared his throat and tried to speak over the grumbling of the bus’s engine.
“We’ll stop at 109 East Palace, Mrs. McKibbin’s place, where you all checked in before coming to the Hill. The bus will head back at 1900—that’s seven o’clock tonight, for you civilians.”
Or for anyone not used to European time, Fox thought.