Born Mar. 21, 1884, in Overisel, Michigan; died Nov. 12,1944, in Cambridge, Massachusetts. American mathematician. Member of the National Academy of Sciences in Washington.
Birkhoff was an assistant, then a professor at Harvard University (from 1912). He contributed works in statistical mechanics (ergodic theorems), theoretical mechanics (he established stability criteria of motion and the existence of periodic motion), and also a general theory of differential and difference equations, and a theory of dynamic systems. In his studies in mechanics he applied extensively the methods of topology and set theory.