The problem of infinite regress has been around for a while, as the idea of an infinite past seems to lead to absurdities. While the big bang model seemed to have removed the idea of an eternal universe, certain inflation models bring it back. Eternal inflation is one example. The evidence we have for the big bang is explained in terms of a local inflation event, which occured some 13.7 billion years ago. While our universe was created and had a beginning, the creation took place in a pre-existing space-time, which itself may have existed forever. While this seems to solve the need for a beginning of our universe, the pre-existing space-time it emerged from would also be expanding, and if finite could be traced back to a beginning itself. So for an eternal inflationary universe, it seems one would need an infinite volume of space. So space and time would be infinite. There seem to be other problems with the idea of an infinite past, which this thread hopefully will cover. Thoughts?