Oral Histories

In 1943, J. Robert Oppenheimer recruited American physicist Robert Bacher to join the Manhattan Project as head of the experimental physics division at Los Alamos. Bacher went on to direct the bomb physics division at Los Alamos from 1944 to 1945, helping oversee the design of the implosion bomb, known as “Fat Man,” that was dropped on Nagasaki. In this interview, Bacher recalls how the Los Alamos laboratory was forced to shift gears from the gun-type design for the plutonium bomb to the implosion-type method. He also describes his post-war service as a member of the Atomic Energy Commission.

Marshall Rosenbluth was an American physicist who worked in the theoretical division at Los Alamos from 1950 to 1956. In this interview, Rosenbluth addresses the theoretical issues involved in designing both the atomic and hydrogen bombs. He discusses how the pressure to create a nuclear bomb before the Soviet Union affected work in the laboratory, especially in performing and checking calculations. Rosenbluth also recounts his experiences during the nuclear weapons tests at Los Alamos and Bikini Atoll. He recalls the roles of top scientists, like Edward Teller, Hans Bethe, Enrico Fermi, and Carson Mark, in the building of the hydrogen bomb. He also explains how funding and other external factors affected the hydrogen bomb’s design.

In this rare interview, J. Robert Oppenheimer talks about the organization of the Manhattan Project and some of the scientists that he helped to recruit during the earliest days of the project. Oppenheimer discusses some of the biggest challenges that scientists faced during the project, including developing a sound method for implosion and purifying plutonium, which he declares was the most difficult aspect of the project. He discusses the chronology of the project and his first conversation with General Leslie Groves. Oppenheimer recalls his daily routine at Los Alamos, including taking his son Peter to nursery school.

In this interview, General Groves discusses the start of the Manhattan Project. He remembers the troubles he had working with Leo Szilard and Eugene Wigner and the importance of redundancy in designing the bomb and plants like the T-Plant. He recounts how the Project came about in the first place, and the early discussions about how to proceed with uranium enrichment, plutonium production, and bomb development.