Walter M. Elsasser

Walter Maurice Elsasser
Elsasser in 1989
Born	20 March 1904 Mannheim, German Empire
Died	14 October 1991 (1991-10-15) (aged 87) Baltimore, United States
Fields	Physics Theoretical biology
Known for	Dynamo theory Complex system biology
Influenced	Theoretical biology Nobel laureates
Notable awards	National Medal of Science (1987) William Bowie Medal (1959) Arthur L. Day Medal (1979)

Walter Maurice Elsasser (March 20, 1904 – October 14, 1991) was a German-born American physicist considered a "father" of the presently accepted dynamo theory as an explanation of the Earth's magnetism. He proposed that this magnetic field resulted from electric currents induced in the fluid outer core of the Earth. He revealed the history of the Earth's magnetic field through pioneering the study of the magnetic orientation of minerals in rocks.

The Olin Hall at the Johns Hopkins University has a Walter Elsasser Memorial in the lobby.

Elsasser was born in 1904 in Mannheim, Germany. Before he became known for his geodynamo theory, while in Göttingen in the 1920s, he had suggested the experiment to test the wave aspect of electrons. This suggestion of Elsasser was later communicated by his senior colleague from Göttingen (Nobel Prize recipient Max Born) to physicists in England. This explained the results of the Davisson-Germer and Thomson experiments later awarded with the Nobel Prize in Physics. In 1935, while working in Paris, Elsasser calculated the binding energies of protons and neutrons in heavy radioactive nuclei. Wigner, Jensen and Goeppert-Mayer received the Nobel in 1963 for work developing out of Elsasser's initial formulation. Elsasser therefore came quite close to a Nobel prize on two occasions.