"Gap" is an understatement. The preponderance of scientific evidence only explains material origins "within" our universe. There is no evidence of where the universe's original substance came from.

Although I think quantum fluctuations theory is the best idea going for the mechanics of how the universe came to be (as Tony asserts), quantum foam is not the same thing as coming from nothing. Quantum foam is very much something. It's not the answer for origins, IMO.

For what it's worth, the biblical allegory of the creation event is as ancient as it gets. Genesis 1 doesn't claim to be scientific proof. It's one of hundreds of ancient origin stories from all over the world. Ancient people wondered about existential questions, just like we do, but they didn't have the tools to sort them out. I am trying to understand why this is an issue for an inquisitive guy like you.