History of creationism the universe was concentrated into a single point, a "primeval atom" where and when the fabric of time and space came into existence. However, in the 1920s and 1930s almost every major cosmologist subscribed to a view that the universe is in an eternal steady state. After Lemaître proposed his theory, some scientists complained that its assumption that time had a beginning amounted to a reimportation of religious concepts into physics. When the expression "Big Bang" was coined by Fred Hoyle in 1949, he meant it to be slightly pejorative, but the term stuck and gained currency. Lemaître himself concluded
Big Bang nucleosynthesis conditions. The denser the initial universe was, the more deuterium would be converted to helium-4 before time ran out, and the less deuterium would remain. There are no known post-Big Bang processes which can produce significant amounts of deuterium. Hence observations about deuterium abundance suggest that the universe is not infinitely old, which is in accordance with the Big Bang theory. During the 1970s, there were major efforts to find processes that could produce deuterium, but those revealed ways of producing isotopes other than deuterium. The problem was that while the concentration of deuterium in the universe is consistent with