Enrico Fermi was a physicist who was very important to the discovery about that atom led to the splitting of the atom and the harnessing of its heat into an energy source. Fermi worked very diligently on the Manhattan Project to create an atomic bomb. He did much studying into experimenting with atoms, the slowing down of the neutrons, and the nuclear chain reactions. After the war was done he thought the human toll from the bombs were much too large. Fermi argued against the development of a hydrogen bomb, but it was built anyways.