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Birkhoff, George David

Born Overisel, Michigan, USA, 21 March 1884

Died Cambridge, Massachusetts, USA, 12 November 1944

American mathematician George Birkhoff developed two theorems with astronomical applications, one (the ergodic theorem) relevant to systems where one wants to take averages over time and space, and one (Birkhoff's theorem) showing that some results of Newtonian gravitation also apply to general relativistic models of the Universe under certain circumstances. He was the son of David Birkhoff, a doctor, and Jane Gertrude Droppers. At the age of 12, Birkhoff entered the Lewis Institute, a West Side Chicago liberal arts and sciences college that merged in 1940 with the Armour Institute to become what is now the Illinois Institute of Technology. In 1901, a year before his graduation from Lewis Institute, he began a correspondence with mathematician Harry Vandiver on number theory that would lead to his first publication in 1904.

Upon graduation from Lewis Institute,