Hans Bethe
Born on 2 July 1906 in Strasbourg (then part of Germany), Hans Bethe was a Nobel laureate who made major contributions to nuclear astrophysics, quantum electrodynamics, and national defense. After completing his doctorate in physics under the guidance of Arnold Sommerfeld at the University of Munich in 1928, Bethe was awarded a Rockefeller fellowship, which allowed him to spend 1930–31 in Cambridge working with Ralph Fowler and then in Rome with Enrico Fermi. When Adolf Hitler rose to power in 1933, Bethe, who was of Jewish ancestry, was dismissed from his position as an assistant professor at the University of Tübingen. He accepted a temporary lectureship in Manchester, UK, before emigrating to the US in 1935 to join the faculty of Cornell University, where he would remain for the rest of his life—teaching for 40 years and retired for 30. Over the next several years Bethe published a number of seminal papers, including three for Reviews of Modern Physics (1936–37), which provided such complete coverage of nuclear physics that they became known as Bethe’s Bible; his landmark 1939 paper, “Energy production in stars ,” for which he would be awarded the 1967 Nobel Prize in Physics; and two in the early 1940s that focused on wartime topics, one on armor penetration and shielding and the other on the physics and chemistry of shock waves. After becoming an American citizen in 1941, Bethe joined the Manhattan Project and became head of the Los Alamos laboratory’s theoretical division. Although Bethe did not support the development of the hydrogen bomb, he cooperated with US efforts against Nazi Germany. After the war he returned to Cornell, where he continued his drive to make it a world center for high-energy particle physics. He also became a prominent advocate and spokesperson for nuclear disarmament . Bethe died in 2005 at age 98; Physics Today published a special issue about Bethe in October 2005. (Photo credit: AIP Emilio Segrè Visual Archives, Physics Today Collection, Fermi Film Collection)
Date in History: 2 July 1906