What does the BGV theorem say?

[Jim]

@Rumraket

What does Vilenkin mean by a beginning? Does he mean the universe at first did not exist at all and nothing did, and then later it suddenly existed?

Or does he simply mean that the universe has a finite age, and thus a first “moment”, or instance, on the axis of time?

Probably the later, although it’s hard to say for sure. But either way, it means an initial event which I would say cries out for an explanation.