...why do people like Stephen Hawking talk about things/events "before" the Big Bang? If time (as part of spacetime) was created with this event, it also marks the point in time that had no "before", doesn't it?
Because they're using the term "Big Bang" properly, to refer, not to an "initial singularity" in idealized models that we know don't correctly describe the very, very early universe, but to the hot, dense, rapidly expanding state that is the earliest state of the universe for which we have good evidence. We don't know for sure what preceded that state, but the current best hypothesis is that it was preceded by an era of inflation.why do people like Stephen Hawking talk about things/events "before" the Big Bang?
If you mean, is there spacetime "before" the Big Bang when that term is used properly, yes, there is. As I said, we don't know for sure what occupies the spacetime before the Big Bang, but our best current hypothesis is that it was an era of inflation.doesn't that usage imply the assumption that normal physics prevailed during that process, i.e. that spacetime was "intact" enough to give a notion of a "before"?
Disregarding the Big Bang event for a moment, I find that topic incredibly interesting from a standpoint of causality. At least to me, causality implies the requirement of time. So, if it is nonsensical to ask "what was before spacetime", then isn't nonsensical to ask "what casued/created spacetime"?There is no such thing.