Alexander Friedmann
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Alexander Alexandrovich Friedmann (also spelled Friedman or Fridman; Russian:Алекса́ндр Алекса́ндрович Фри́дман) (June 16 [O.S. 4], 1888 – September 16, 1925) was a Russian and Soviet physicist and mathematician. He is best known for his pioneering theory that the universe was expanding, governed by a set of equations he developed now known as the Friedmann equations.