Copenhagen

When a job at Leipzig University opened, both Heisenberg and Schrodinger were shortlisted. Having published his paper on uncertainty and having worked with Bohr, Heisenberg was awarded the position and became the youngest full professor in Germany. Margrethe believes this shows why he came to Copenhagen in 1941: “to show yourself off to us” (47). In 1924 Heisenberg was a humble assistant. In 1941 he returned as “the leading scientist in a nation that’s conquered most of Europe” (47), to show off that he was working on a vital and secret research project. Heisenberg came to Copenhagen to flaunt his important, wonderful, new moral dilemma to Bohr, a man who is obsessed with moral dilemmas and paradoxes.

Margrethe sees through the lies Heisenberg tells himself. He is “no hero of the resistance” (47), though he claims to have worked on the Nazi atomic project to delay and confound it. Rather, Heisenberg was obsessed with the science of the project and ignored the wider questions around his actions in a desperate race to solve the mathematics of the problem. Heisenberg defends himself, asking whether he should have stood up to Hitler and got himself killed, or whether Bohr should have dived into the water when his son Christian died in a boating accident and drowned alongside him. Bohr says, “perhaps. Perhaps not” (48).

Heisenberg asks—if Bohr was convinced that Heisenberg was going to develop an atomic bomb for the Nazis—why did Bohr not kill Heisenberg in Copenhagen in 1941? All he had to do was talk about what Heisenberg had said: Bohr’s house was bugged by the Gestapo, who would have killed Heisenberg for revealing state secrets. The idea never occurred to Bohr. Margrethe tells Heisenberg that he has a natural affinity for uncertainty.

When Heisenberg mentions that his return in 1947, after the war and after he was beaten to the finish line of the atomic project, must have seen him “cut a gratifyingly chastened figure” (49). Margrethe dismisses this, saying that Heisenberg wanted to demonstrate that—once again—he had come out on top. She can no longer keep her thoughts to herself; she has been driven mad by Heisenberg—who is like a son to her—constantly crossing the lines he has asked them to establish. The protection that Heisenberg had promised in 1941 did not last long, and by 1943, Bohr had to flee Denmark to keep his life. Heisenberg protests, saying that he tried to warn them. Margrethe says that for all their hopes and ambitions, the work of the 1920s physicists succeeded only in producing “a more efficient machine for killing people” (49).

By way of protest, Heisenberg says that he is not the one who made the bomb. Margrethe tells him this was only because he did not understand the physics. Heisenberg insists that he understood, but secretly, so as to keep the bomb from the Nazis. Heisenberg insists that he told one person, explaining how the bomb had worked when news reached them that America’s bombs had fallen on Nagasaki and Hiroshima. Heisenberg believes the British were recording this conversation. Bohr presses him further, revealing that his mathematics were wrong and his predictions misplaced. His tiny failures doubled over the years, branching out “until they were large enough to save […] any of the cities that we never dropped our bomb on” (52).

Bohr asks Heisenberg why he failed to make this particular calculation. Heisenberg admits that the idea never occurred to him and turns the question back on Bohr, asking him to “tell us why you didn’t calculate it and we’ll know why I didn’t” (53). Margrethe answers for her husband: It was because Bohr was not trying to build a bomb. They agree to work on one more draft of the reason why Heisenberg came to Copenhagen in 1941.

The two men meet again on Bohr’s doorstep in 1941. As Heisenberg enters and makes small talk, he sees himself from an exterior perspective, making awkward conversation. Bohr and Heisenberg walk together and, once again, Heisenberg asks Bohr whether physicists have the moral right to work on atomic projects. The question is like an atomic explosion, destroying the friendship between the two men. But this time, Bohr halts the memory. He ponders what would have happened if, instead of reacting with anger, he stopped to ask Heisenberg about the project. In doing so, he might have prompted Heisenberg to ask questions that he had not previously asked, thus solving the problem. As such, “a very different and very terrible world begins to take shape” (55). Heisenberg wonders whether he should thank Bohr for leaving him to misunderstand the issue.

Bohr recollects the night he fled Denmark. Thousands of Jews were to be rounded up the next day, but he fled into hiding after receiving a tip from a man in the German embassy. The man was Georg Duckwitz, closely tied to Heisenberg. When Bohr tries to thank Heisenberg, Heisenberg denies any involvement. After that, Bohr fled to America and helped with the building of an atomic bomb while Heisenberg protected Bohr’s laboratories in Denmark which—ironically—contained everything he needed to make material for a bomb of his own. Bohr mentions that he played a part in the death of 100,000 people. Margrethe tells him he did nothing wrong, and Heisenberg agrees.

Heisenberg remembers when he met an SS officer on the way home from Haigerloch near the end of the war. He traveled through Germany on a bicycle, surveying the destruction en route to seeing his family. He was stopped by a fanatical SS officer, who accused him of being a deserter. He bribed the man with American cigarettes and was allowed to continue on his journey. He falls silent remembering his ruined homeland; Bohr and Margrethe pity Heisenberg, seeing him like a “lost child” wandering along a road, like the child they lost themselves. The characters agree that eventually everything will die, including their own children. They wonder what will be left of the world, but Heisenberg sees the world preserved by the moment in Copenhagen, “by some event that will never quite be located or defined” (58).