Hans Albrecht Bethe (1906–2005) was a Nobel physicist and leader in efforts to promote social and ethical responsibilities among scientists and engineers. Born in Strassburg, Germany (now Strasbourg, France), on July 2, Bethe received his doctorate from the University of Munich in 1928 and began teaching at Cornell University in 1935, where he continued throughout his career. Bethe died in Ithaca, New York, on March 6. In 1938 he published three papers on nuclear physics that became known as "Bethe's Bible," and he received the 1967 Nobel Prize for discoveries concerning energy production in stars.

Hans Bethe, (1906–2005). An Alsatian-born American theoretical physicist, Bethe is a prolific and creative contributor to several vital fields of nuclear physics. He also discovered the mechanism of energy production by stars, including the sun. (AP/Wide World Photos.)

During World War II, the U.S. government recruited Bethe to work on military technologies, and in 1943 he was made...