durn, it's tricky to discuss, ain't it? The problem is, we can use language to refer to stuff that has no actual existence. "Cosmic ground" or "emptiness" aren't exactly 'places'...but they BECOME places after something fill them...except, by being filled, they are no longer what they were...or weren't, as it were.

Philosophers like Husserl, Heigegger, Wittgenstein, etc...spend many pages trying to discuss "being" in some way that we can wrap our poor heads around, but it seldom does much good for most folks. Physicists and Astronomers have arugued for years whether 'space' were curved, flat,.. and if curved, which way, and they have changed their collective minds several times.

And far from being satisfied with deciding what the "Universe" is, or how big it is, or what is 'outside' it, some masochists want to postulate more the one universe!

It's all pretty durn big, and pretty durn confusing!