ScienceWeek

EUGENE WIGNER (1902-1995) AND THE ATOMIC BOMB

The following points are made by Alvin M. Weinberg (Physics Today 2002 October):

1) Eugene Wigner (1902-95), the founder of nuclear engineering, led the group that designed the first very high-powered nuclear reactors, which were built at Hanford, Washington, for the production of the isotope plutonium-239. When fission was discovered late in 1938, Wigner was the completely prepared mind. In 1936 he had codiscovered the Breit-Wigner formula for the shape of neutron resonances in nuclei. And, through his friendship with Leo Szilard (1898-1964), he had been thinking since 1934 about the possibility of releasing nuclear energy. Szilard had postulated that a chain reaction based on neutrons would be possible, and he took out a British admiralty patent on the concept. Wigner was impressed with Szilard's general idea. He says in his memoirs that he thought long and hard to see whether some kind of law of nature -- somewhat like the law of conservation of energy -- would preclude the possibility of a nuclear chain reaction.(1) He decided as early as 1936 that no such law existed, and in his unpublished speech that year to the Gamma Alpha Society at the University of Wisconsin, he said that within five years scientists would figure out how to release nuclear energy. He later wrote that he had no reason for specifying five years, but he was confident that the nuclear community would discover a neutron-initiated nuclear reaction that would produce both energy and neutrons.(2)

2) Once Otto Hahn (1879-1968) and Fritz Strassman (1902-1980) discovered fission in 1938, Wigner and fellow Hungarians Szilard, Edward Teller, and John von Neumann (1903-1957) realized that nuclear bombs were possible. Wigner and Szilard, whose European-Hungarian background taught them what happens when a country is run by dictators such as Adolf Hitler, became obsessed in their desire to push forward the development of the atomic bomb. By early 1939, war in Europe was imminent. Wigner realized that humanity was in a struggle with the forces of evil, and that whoever made the bomb first would rule the world. Therefore, he, along with Szilard and Teller, decided that they would have to enlist the US government in the project to develop the atomic bomb. Wigner suggested that he and Szilard persuade Albert Einstein to write a letter apprising President Franklin Roosevelt of the grim possibility that was opened up by the discovery of fission. Once the letter was written in August 1939, they enlisted an economist from New York City, Alexander Sachs, to convey it to Roosevelt.(3-5)

References (abridged):

1. Wigner kept a diary, beginning in 1941, which is published as "Memoir of the Uranium Project" in A. M. Weinberg, ed., The Collected Works of Eugene Paul Wigner, vol. 5, Springer-Verlag, New York (1992). The memoir is an excellent history of the origins of Hanford.

2. See p. 24 in A. M. Weinberg, ed., The Collected Works of Eugene Paul Wigner, vol. 5, Springer-Verlag, New York (1992).

3. See, for example, M. Bundy, Danger and Survival: Choices about the Bomb in the First Fifty Years, Random House, New York (1988), p. 35.

4. M. G. I. Boissevan et al., in ref. 2, p. 297.

5. E. C. Creutz et al., in ref. 2, p. 631.