The universe expands! We can all agree on that.
Some say that the universe is all there is. So the universe expands into what exactly?
What I am trying to figure out is, if there is some sort of void beyond the universe? And if there is, the universe is not all there is, right?
Even a void without space, matter and time is still "something".
The problem of a universe with no void around it, is that it does not expand. It stretches. And if spacetime stretches, everything grows in size. Including matter.
Particles do not change charge or size. If they did, we would be able to see it. So there must be a void out there!