Oppenheimer, J. Robert

1. An American physicist of the twentieth century. Oppenheimer led the research and development of the atomic bomb (see also atomic bomb ) and was head of the Manhattan Project .

Notes

In the early 1950s, Oppenheimer's opposition to building the hydrogen bomb and his past association with leftists led to a hearing regarding his security clearance. Although the committee found that he was a “loyal citizen,” his security clearance was not restored, and he was barred from government research. Oppenheimer's chief opponent in the scientific community at this time was Edward Teller .