German-born US physicist who was awarded the 1943 Nobel Prize for Physics for his use of molecular beams to establish the existence of atomic magnetic moments.
The son of a prosperous grain merchant, Stern was educated at the University of Breslau, where he obtained his PhD in 1912. He worked with Einstein as a postdoctoral student in Prague and Zürich and, after service with the German army during World War I, taught at the University of Rostock (1921–23). In 1923 he moved to the University of Hamburg as professor of physical chemistry, but with the rise of the Nazis in 1933, as a Jew, he decided to emigrate to the USA. He took up an appointment with the Carnegie Institute of Technology, Pittsburgh, which he held until his retirement in 1945. On his retirement Stern moved to Berkeley, California, where he died of a heart attack, aged eighty-one, on his daily visit to the cinema.
In 1920–21, in cooperation with Walter Gerlach, Stern attempted to check Arnold Sommerfeld's suggestion that some atoms have magnetic moments, as required by his version of the quantum theory. Stern passed beams of silver atoms through a nonuniform magnetic field. As predicted, the beam split into two separate parts, thus establishing Sommerfeld's theory. Using similar techniques Stern went on to measure the magnetic moment of the proton (1933) and the deuteron (1934).
Subjects: Science and Mathematics — Contemporary History (Post 1945).