any model of the universe deduced from a homogeneous, isotropic solution of Einstein's field equations without a cosmological constant. Such models form the mathematical basis for many modern cosmologies and provide for expansion or contraction of the universe.
Origin of Friedmann model
named after Alexander Friedmann, (1885–1925), Russian mathematician, who made the necessary calculations in 1922
Also called Friedmann universe.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019