The big bang theory says that time began with the big bang. Is that correct? Then does that mean that those who describe the big bang theory as an idea that something comes from nothing are incorrect? If time began with the big bang doesn't that mean there never was a time when there was nothing?

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Not quite correct. Cyclic theories still posit a Big Bang, but they also posit a cycle of expansions and collapses. This is not something I know much about but you can read a bit more here

If we suppose that the non-cyclic Big Bang model is correct, then in at least one sense, the universe isn't a case of getting something from nothing: it's not an example of matter appearing uncaused in a universe where there are earlier times with no matter. Of course, that's consistent with there being no explanation of why there's matter/energy at all. That may not quite amount to getting something from nothing, but it's an idea that doesn't sit well with everyone. Some versions of the Cosmological Argument are meant to explain why contingent things (like the physical things we're familiar with) exist. The explanations typically appeal to the existence of a Necessary Being—one who's very nature requires that it exist. If there's no such being, then it might be that there's no explanation for why contingent things exist, even if there wasn't a time when there were no contingent things.

I can't resist responding to one thing that Prof. Stairs says in his excellent reply: "If there's no such [necessary] being, then it might be that there's no explanation for why contingent things exist." I used to think that myself. But as I thought more about the question "Why do any contingent things exist?" I concluded that the question has a very simple answer -- indeed, many simple answers -- if it's a well-posed question in the first place, and those answers have nothing to do with any necessary being. I try to explain why in this paper.

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