John Harry Williams
John Harry Williams (July 7, 1908 – April 18, 1966) was a Canadian‑American physicist and a professor at the University of Minnesota. He helped with the Manhattan Project during World War II and later became an Atomic Energy Commissioner.
Born in Asbestos, Quebec, Williams grew up with three brothers. After high school in Kelowna, British Columbia, he earned a BS from the University of British Columbia in 1928. He then went to the University of California, Berkeley, for graduate work, earning an MA in 1930 and a PhD in 1931. He published his first paper during his first year of graduate study. Williams did a postdoctoral stint at the University of Chicago (1931–1933) before joining the University of Minnesota as a physics instructor, becoming a full professor by 1946.
Early in his career, Williams studied the ionization and dissociation of gases, but he soon moved into nuclear physics. He and colleague William H. Wells worked on a Van de Graaff generator, first reaching 1 MeV and then expanding to 3 MeV with Rockefeller Foundation funding in 1937 for nuclear research.
During World War II, Williams became a U.S. citizen and joined the Office of Scientific Research and Development. From 1943 to 1946 he led the Electrostatic Generator Group for the Manhattan Project and worked on neutron cross sections for the bomb program. He was deputy director of the Trinity test in 1945 and helped with the Bikini Atoll experiments in 1946 before returning to Minnesota.
After the war, Williams helped secure funding for a 50‑MeV proton accelerator at the University of Minnesota, which was built in the 1950s. He held several leadership roles, including president of the Midwest Universities Research Association (1956–1957) and director of the research division of the Atomic Energy Commission (AEC) in 1958. He was named an Atomic Energy Commissioner by President Dwight D. Eisenhower in 1959 and served on the AEC’s General Advisory Committee from 1960 to 1966. He was elected to the National Academy of Sciences in 1961 and served as president of the American Physical Society in 1963. In 1965 he became president of the Argonne Universities Association.
Williams married Vera Martin in 1928, and they had three children. He battled cancer from 1951, undergoing treatment that brought some control but with flare‑ups for the rest of his life. He died of pneumonia in Minneapolis in 1966. He received honorary doctorates from the University of British Columbia and the Pennsylvania Military College.
This page was last edited on 3 February 2026, at 16:08 (CET).