# Otto Stern

    Otto Stern was also the pen name of German women's rights activist Louise Otto-Peters (1819–1895).
Otto Stern (German: ; 17 February 1888 – 17 August 1969) was a German-American physicist. He is the second most nominated person for a Nobel Prize, with 82 nominations during the years 1925–1945. In 1943, he received the Nobel Prize in Physics "for his contribution to the development of the molecular ray method and his discovery of the magnetic moment of the proton".

## Biography

Stern was born into a Jewish family in Sohrau (now Żory) in the Province of Silesia, the German Empire's Kingdom of Prussia. His father was Oskar Stern (1850–1919), a mill owner, who had been living in Breslau (now Wrocław) since 1892. His mother Eugenia née Rosenthal (1863–1907) was from Rawitsch (now Rawicz) in the Prussian Province of Posen. Otto Stern had a brother, Kurt, who became a noted botanist in Frankfurt, and three sisters. He studied in Freiburg im Breisgau, Munich and Breslau.
Stern completed his studies at the University of Breslau in 1912 with a doctoral dissertation in physical chemistry under supervision of Otto Sackur on the kinetic theory of osmotic pressure in concentrated solutions. He then followed Albert Einstein to Charles University in Prague and in 1913 to ETH Zurich. Stern served in World War I doing meteorological work on the Russian front while still continuing his studies and in 1915 received his Habilitation at the University of Frankfurt. In 1921 he became a professor at the University of Rostock which he left in 1923 to become director of the newly founded Institut für Physikalische Chemie at the University of Hamburg.
In 1930, Stern received an LL.D. degree from Berkeley, where he was a frequent visiting professor during the 1930s, becoming close colleagues with members of the Berkeley faculty, including chemistry dean Gilbert Lewis, whom Stern would nominate for the Nobel Prize in Chemistry in 1933. After resigning from his post at the University of Hamburg in 1933 because of the Nazis' Machtergreifung (seizure of power), he found refuge in the city of Pittsburgh becoming a professor of physics at the Carnegie Institute of Technology.
As an experimental physicist Stern contributed to the discovery of spin quantization in the Stern–Gerlach experiment with Walther Gerlach in February 1922 at the Physikalischer Verein in Frankfurt am Main. With his life-long collaborator Immanuel Estermann, he demonstrated of the wave nature of atoms and molecules; measurement of atomic magnetic moments; discovery of the proton's magnetic moment; and development of the molecular beam method which is utilized for the technique of molecular beam epitaxy.
He was awarded the 1943 Nobel Prize in Physics, the first to be awarded since 1939. It was awarded to Stern alone, "for his contribution to the development of the molecular ray method and his discovery of the magnetic moment of the proton" (not for the Stern–Gerlach experiment). The 1943 prize was actually awarded in 1944.
Stern was elected to the United States National Academy of Sciences in 1945 and the American Philosophical Society in 1946.
After Stern retired from the Carnegie Institute of Technology, he moved to Berkeley, California. He was a regular visitor to the physics colloquium at Berkeley. He died of a heart attack in Berkeley on 17 August 1969.
The Stern-Gerlach-Medaille of the Deutsche Physikalische Gesellschaft awarded for excellence in experimental physics is named after him and Gerlach.
His niece was the crystallographer Lieselotte Templeton.