4 ms·
Who says the universe has bounds? The classic analogy is of an inflating balloon. If you make two marks on the balloon, they'll expand away from each other, but
by Cushman 15y ago
Who says the universe has bounds? The classic analogy is of an inflating balloon. If you make two marks on the balloon, they'll expand away from each other, but neither one is the center.
Of course AFAIK there isn't any solid proof for the "finite, unbounded" idea, mostly just speculation. But it was Einstein's thing so we (laymen ;) take it pretty seriously.
- sliverstorm 15y agoYou're saying that the space inside the balloon is not part of the Universe?
- Cushman 15y agoWell, Einstein is ;) But yeah, for the sake of the analogy we're talking about a 2-d universe which is the surface of the balloon, nothing else exists.
- sliverstorm 15y agoSo objects in the Universe are not traveling because they have velocity, rather, "space itself" is expanding?
- Cushman 15y agoI don't think I understand your question— both are true?