In the 2023 film Oppenheimer, during the Manhattan project to develop the nuclear bomb, one of the concerns was whether the nuclear explosion created during a test might create such high temperatures that it leads to the nuclei of nitrogen atoms in the atmosphere fusing together and triggering a chain reaction that essentially sets the atmosphere on fire, frying the entire planet. Oppenheimer tells general Leslie Groves, the director of the project, that the calculations of Arthur Compton showed that the chance of such a thing happening was less that three in a million, and thus acceptable. When Groves said that he was hoping that the answer would be zero, Oppenheimer replied that you could not expect such an answer from theory alone..
While the idea that theory can never give you absolute certainty about anything is correct, the actual story is more complicated. It turns out that the Oppenheimer-Compton story is based on an article written by Pearl S. Buck, based on an interview she had with Compton, and some of the details are apocryphal. Hans Bethe, head of the theoretical program at Los Alamos, who had shown how fusion reactions lay behind the energy production of stars, had concluded early on that the chance of a runaway fusion reaction igniting the air was so small as to not be worth worrying about.
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