Oppenheimer, J. Robert cultural definition

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.

• 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.