Sir Rudolph Peierls, whose work on nuclear fission contributed to the development of the atomic bomb, died Tuesday in Oxford, England. He was 88.
At the University of Birmingham in Britain, the German-born Peierls and Austrian-born Otto Frisch in 1940 calculated that a bomb was possible if the isotope uranium-235 could be separated from dominant uranium-238.
The "Frisch-Peierls Memorandum" set in motion the British atomic effort and stimulated America's Manhattan Project that led to the explosion of the first atomic bomb at Alamogordo, N.M., in July 1945.
Hailed as a founding father of the nuclear age, Peierls became president of the Atomic Scientists' Association that campaigned for international control of nuclear weapons.
He was knighted in 1968 and retired from his university post in 1974.