The Making of the Atomic Bomb: 25th Anniversary Edition

by Richard Rhodes

A discovery in physics opened the field to new possibilities while discoveries Szilard made in literature and utopianism opened his mind to new approaches to world salvation. On February 27, 1932, in a letter to the British journal Nature, physicist James Chadwick of the Cavendish Laboratory at Cambridge University, Ernest Rutherford’s laboratory, announced the possible existence of a neutron. (He confirmed the neutron’s existence in a longer paper in the Proceedings of the Royal Society four months later, but Szilard would no more have doubted it at the time of Chadwick’s first cautious announcement than did Chadwick himself; like many scientific discoveries, it was obvious once it was demonstrated, and Szilard could repeat the demonstration in Berlin if he chose.61, 62) The neutron, a particle with nearly the same mass as the positively charged proton that until 1932 was the sole certain component of the atomic nucleus, had no electric charge, which meant it could pass through the surrounding electrical barrier and enter into the nucleus. The neutron would open the atomic nucleus to examination. It might even be a way to force the nucleus to give up some of its enormous energy.