Interview with Robert F. Christy

Abstract

Robert F. Christy was born in Vancouver in 1916, received his undergraduate education at the University of British Columbia, and took his Ph.D. degree with J. Robert Oppenheimer at Berkeley in 1941. He was an early participant on the Manhattan Project, working with Enrico Fermi at the Metallurgical Laboratory of the University of Chicago on the first atomic pile. In 1943 he went to Los Alamos as a member of the Theoretical Division under Hans Bethe, where he devised what came to be known as the Christy bomb, or the Christy gadget--the plutonium implosion device tested at Alamogordo on July 16, 1945. After the war he returned briefly to the University of Chicago, where he and his wife shared living quarters for a time with Edward Teller and his wife. Caltech was then seeking to build up its theoretical physics faculty, and Oppenheimer, who was teaching there part time, recommended that the institute hire Christy. In 1946 Christy accepted Caltech's offer of an associate professorship. He worked chiefly on the application of theory to cosmic-ray experiments in particle physics, later moving into nuclear physics and astrophysics, including important work in the 1960s on the pulsations of RR Lyrae stars, which are similar to but smaller than the Cepheid variables used as cosmic yardsticks. In 1967 this work earned Christy the Eddington Medal of the Royal Astronomical Society. In 1970, Christy became Caltech's provost, a post he held for the next ten years. After Caltech president Harold Brown left to join the Carter Administration as Secretary of Defense in 1977, Christy was also acting president of the institute, until the advent of Marvin L. (Murph) Goldberger a year later. In the mid-1980s he became a member of the National Research Council's Committee on Dosimetry, which investigated the radiation effects of the Hiroshima and Nagasaki bombs. In the interview Christy recalls his childhood in British Columbia; his undergraduate years at the University of British Columbia; his graduate work with J. Robert Oppenheimer at Berkeley; and his work on the Manhattan Project, first with Enrico Fermi at the Metallurgical Laboratory of the University of Chicago and then as a member of the Theoretical Division at Los Alamos. He recounts his wartime work on the critical assembly for the plutonium bomb ("the Christy bomb"); the Alamogordo test, July 16, 1945; the postwar concerns of ALAS (Association of Los Alamos Scientists); his brief return to the University of Chicago and move to Caltech; friendship with and later alienation from Edward Teller; work with Charles and Tommy Lauritsen and William A. Fowler in Caltech's Kellogg Radiation Laboratory; Freeman Dyson's Orion Project; work on the meson and RR Lyrae stars; fellowship at Cambridge University; 1950s Vista Project at Caltech; his opposition to the Strategic Defense Initiative; and his post-retirement work for the National Research Council's Committee on Dosimetry and on inertial-confinement fusion.