BETHE, Hans Albrecht (1906- ), German-born American physicist and Nobel laureate, noted for his contributions to theories of stellar energy production. Bethe was born in Strasbourg, France (then a
part of Germany), and educated at the University of Frankfurt and the University of Munich, from which he received a Ph.D. degree in 1928. He taught physics in Germany and England, and then in the U.S. from 1935 at
Cornell University. He became a U.S. citizen in 1941. Beginning in 1943, he worked at Los Alamos, N.Mex., on the atomic-bomb project and later on the hydrogen bomb. At the same time he continued his work for the
peaceful use and international control of nuclear energy. A prime advocate of the partial test-ban agreement signed by the U.S., the Soviet Union, and Great Britain in 1963, he became an opponent of the Strategic
Defense INITIATIVE (q.v.) , proposed by the U.S. in the 1980s. Bethe was awarded the 1967 Nobel Prize in physics for his studies of the production of energy by the sun and other stars. He postulated that thermonuclear
reactions in which hydrogen is converted into helium were the source of this energy.