A small boy was lost, so he went up to a policeman and said, "I've lost my dad!"
The policeman said, "What's he like?"
The little boy replied, "Chips and beer."
George David BirkhoffDied 12 Nov 1944 at age 60 (born 21 Mar 1884).American mathematician,foremostof the early 20th century, who formulated the ergodic theorem. As the first American dynamicist, Birkhoff picked up where Poincaré left off, gaining distinction in 1913 with his proof of Poincaré's Last Geometric Theorem, a special case of the 3-body problem. Although primarily a geometer, he discovered new symbolic methods. He saw beyond the theory of oscillations, created a rigorous theory of ergodic behavior, and foresaw dynamical models for chaos. His ergodic theorem transformed the Maxwell- Boltzmann ergodic hypothesis of the kinetic theory of gases (to which exceptions are known) into a rigorous principle through use of the Lebesgue measure theory. He also produced a mathematical model of gravity. |
