Georges Lemaître and technology subjects in the December 1932 issue of Popular Science. Lemaître himself also described his theory as "the Cosmic Egg exploding at the moment of the creation"; it became better known as the "Big Bang theory," a pejorative term coined during a 1949 BBC radio broadcast by the astronomer Fred Hoyle, who was then still a proponent of the steady state universe and remained so until his death in 2001. Lemaître's proposal met with skepticism from his fellow scientists. Eddington found Lemaître's notion unpleasant. Einstein thought it unjustifiable from a physical point of view, although he encouraged Lemaître to
Steady state model universe as modeled by Einstein (1917) was unstable and contradicted general relativity. The modern Big Bang theory is one in which the universe has a finite age and has evolved over time through cooling, expansion, and the formation of structures through gravitational collapse. The steady state model asserts that although the universe is expanding, it nevertheless does not change its appearance over time (the perfect cosmological principle); the universe has no beginning and no end. This requires that matter be continually created in order to keep the universe's density from decreasing. Influential papers on steady state cosmologies were published by