[layer8]

It doesn’t expand into anything. It has no edge. It expands within itself, like it’s distorting itself. Alternatively, you can picture it as groups of gravitationally bound objects (= galaxy clusters) moving away from each other everywhere in the universe. It’s a bit like raisins in a cake being carried away from each other by the dough expanding in the oven. Where the cake already fills all space infinitely in all directions, from the very start. Space is the cake dough. There is no “outer” space that space expands into. The geometry of space itself expands.

Still alternatively, imagine an infinitely extended graph paper whose grid size slowly and continuously increases, carrying with it the dots already drawn on it. Since the grid has infinite size from the start, it doesn’t expand into anything. It just expands.

[wutwutwat]

> It doesn’t expand into anything. It has no edge. It expands within itself, like it’s distorting itself

That's not an explanation, that's incoherent ramblings that make zero logical sense

[16bytes]

To paraphrase Feynman, I can't explain to you how the universe expands in terms that you are familiar with because I don't understand it in terms that you are familiar with.

https://www.youtube.com/watch?v=MO0r930Sn_8

It takes effort to understand those fundamental terms, so if you want to understand this, you'll have to meet people halfway instead of rejecting how somebody is trying to explain something to you.

[layer8]

The math from general relativity is crystal clear. It’s just difficult to translate into natural language, because it doesn’t match our intuitions, which are primed by local experiences of non-curved space. You have to question your intuitions, and if you’re serious about it, look into the actual math. It all follows from a few basic assumptions, and is consistent with actual observations to an unmatched degree.