I once made an abstract painting and titled it “The Universe is Expanding”
... because I can’t think of anything more abstract than the fact that the universe is expanding – and the fact that even though it’s expanding – it doesn’t have any boundaries. How can something that can’t be measured get bigger?
My father sent me another link to make my brain explode: Where is the center of the universe. And if the question alone doesn’t make your head spin, then the answer surely will (as do most answers relating to anything about the universe) – at least for me anyway. The answer is of course, there is no center.
(Although at least one of my kids might dispute this theory and insist that, no, there is in fact a center… and if you’re looking at them, then you’re looking right at it)