To my understanding, The Big Bang Theory (BBT) is considered the standard, mainstream theory explaining the origin of the universe. I know that there are alternative theories, and my question is, how discredited, fringe, or false are these theories considered, if at all? Alternatively, how secure is BBT's position as the mainstream, standard theory? Are proponents of other theories considered nuts, outdated, or mainstream? How many physicists are out there who think BBT is either completely wrong or in need of some serious modifications? This is really more of a sociological question than a scientific one. I'm not looking to debate BBT or its alternatives, as I'm unqualified to do so.