Best analogy I heard for it is if you put a load of dots on a balloon, then inflate it. Are the dots getting further away? Yes. Is there just the same amount of rubber between each dot as when you put the dots on? Yes. Can you measure the relative speed of the dots? Yes! But have they actually gone anywhere? No…ish?
Yeah, but in this case is the universe just the dots on the surface of the balloon or is it the whole balloon with its entire volume? Intuitively I think it’s the latter (although there’s probably no “hard” edge that’s bounding the ends of the universe like the rubber of the balloon), and if that’s true, you could measure the speed of one wall getting away from the centre or the speed of two opposite walls getting away from each other.
I could be wrong of course, I’d be happy if someone points out what I might be missing.
Yep I think you have to imagine dots suspended in space inside the balloon to better get what’s going on, and you’re right, the “edge” of the universe is definitely nothing like the surface if the balloon. Probably?
Best analogy I heard for it is if you put a load of dots on a balloon, then inflate it. Are the dots getting further away? Yes. Is there just the same amount of rubber between each dot as when you put the dots on? Yes. Can you measure the relative speed of the dots? Yes! But have they actually gone anywhere? No…ish?
Great analogy, and yeah the “ish” is the fun part!
The fun of justifying a reference frame outside the universe. Sorry I’m getting a headache.
Yeah, but in this case is the universe just the dots on the surface of the balloon or is it the whole balloon with its entire volume? Intuitively I think it’s the latter (although there’s probably no “hard” edge that’s bounding the ends of the universe like the rubber of the balloon), and if that’s true, you could measure the speed of one wall getting away from the centre or the speed of two opposite walls getting away from each other.
I could be wrong of course, I’d be happy if someone points out what I might be missing.
Yep I think you have to imagine dots suspended in space inside the balloon to better get what’s going on, and you’re right, the “edge” of the universe is definitely nothing like the surface if the balloon. Probably?