I referenced a class of problems easily defined via mathematical tools and notation that are seemingly not possible to solve in our universe as an adjacent exam

I referenced a class of problems easily defined via mathematical tools and notation that are seemingly not possible to solve in our universe as an adjacent example for difficult problems that border on our definition of understanding. A problem doesn't have to be undecidable to be realistically unsolvable. For example, I don't think that we can compute TREE(3). Or Graham's number, which is quite a bit smaller. TREE(3) is computable and defined. However, we can't fit it into our universe even if converted every atom into computronium. So do we understand TREE(3)? Surely yes, though at the same time no? How about Rayo's number? As such, I am merely making a statement that at certain scales, to our brains, quantity has a quality of its own. Yes, it is. I've used it for about 15 years now.