One of the recurring metaphors in the play is skiing. Bohr and Heisenberg recollect a vacation they took with fellow physicists; their skiing styles reflected their varying approaches to science. For Bohr, this meant taking a slow and steady approach. For Heisenberg, this meant racing toward the finish line with scant regard for his surroundings. Throughout the play, these metaphors change and evolve.

The first time the men talk about their skiing trip, the memory functions as evidence of the closeness of their relationship. The gentle mockery of each other’s style reflects a close bond in which they can recognize and laugh about their differences. It demonstrates that, at the time, they (and the rest of the scientific community) were faced with far lower stakes. At the time, one’s skiing style was a defining characteristic. During the war years, however, defining characteristics centered on questions or ethics or morality, such as whether one had chosen to work with the Nazis to invent an atomic bomb. The contrast between the two situations illustrates the rapidity with which circumstances changed for the physicists, as well as a sense of nostalgia that suggests both Bohr and Heisenberg longed for the days when the stakes of their work were significantly lower.