History of the Big Bang theory scales, has no preferred directions or preferred places. Hubble's idea allowed for two opposing hypotheses to be suggested. One was Lemaître's Big Bang, advocated and developed by George Gamow. The other model was Fred Hoyle's Steady State theory, in which new matter would be created as the galaxies moved away from each other. In this model, the universe is roughly the same at any point in time. It was actually Hoyle who coined the name of Lemaître's theory, referring to it as "this 'big bang' idea" during a radio broadcast on 28 March 1949, on the BBC Third Programme. It
Chronology of the universe is thought to break down for this epoch due to quantum effects. In inflationary models of cosmology, times before the end of inflation (roughly 10 second after the Big Bang) do not follow the same timeline as in traditional big bang cosmology. Models that aim to describe the universe and physics during the Planck epoch are generally speculative and fall under the umbrella of "New Physics". Examples include the Hartle–Hawking initial state, string landscape, string gas cosmology, and the ekpyrotic universe. As the universe expanded and cooled, it crossed transition temperatures at which forces separated from each other. These phase