"Stanislaw Ulam, a brilliant Polish mathematician from the University of Wisconsin, went to Los Alamos to solve the implosion problem. The problem was to calculate the actions of several explosions to some workable mathematical model. His solution was to surround the plutonium core with high explosives. The high explosives were cast into spheres, called lenses, and wired so they would all fire at the same instant. The pressure caused from the explosions on all sides of the sphere focused the shock waves inward on the plutonium core. The plutonium core compressed in on itself until it reached critical mass and exploded, as proven during the Trinity test"
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