About Alexander Friedmann
Alexander Alexandrovich Friedmann was a Russian and Soviet physicist and mathematician. He originated the pioneering theory that the universe is expanding, governed by a set of equations he developed known as the Friedmann equations. The First Alexander Friedmann International Seminar on Gravitation and Cosmology devoted to the centenary of his birth took place in 1988. In July 1925 he participated in a record-setting balloon flight, reaching an elevation of 7,400 m (24,300 ft).
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