The Beginning of Time

This isn't a physics question; it's about nomenclature. All languages have logical paradoxes that can't be resolved, especially on the subjects dealing with infinity, ironclad limitations, and self-reference. So asking a question like "what comes before the beginning" is akin to dividing by zero in math. It can only be answered by going outside the system or resorting to the answer "undefined." Similarly, if the universe is expanding, what exactly is it expanding into?

This may sound like a nonanswer, but there are lots of things that lie beyond us. We can't hear above a certain range, but insects can. We can't see with much acuity, but birds can. We can't smell with much fidelity, but dogs can. We're limited by our physiology. We can't answer the question "what comes after death?" except by conjecture, and similarly, it's difficult to conceptualize existence suddenly appearing out of nothingness. Chalk it up to another of man's limitations.