3 ms·
> Light, on the other hand, takes billions of years to cross the visible universe Right, and that's just the visible universe. The full extent of the universe
by A_D_E_P_T 2y ago
> Light, on the other hand, takes billions of years to cross the visible universe
Right, and that's just the visible universe. The full extent of the universe is much larger -- I think that the most cautious lower bound estimate is that it's 250x larger. It could be 10^10x larger, or even infinite/unbounded. In such a vastness, the speed limits for light and baryonic matter are perplexingly slow.
- Mistletoe 2y agoAre galaxies and stuff out in that 250x or is it just empty space?
- JdeBP 2y agoIt's not observable by us, so we don't know. The figure is (to simplify) a deduction from what we can see, the observable universe, and the fact that we don't see any of the consequences that there would be in the observable bit if the entire universe were smaller. * https://doi.org/10.1111/j.1745-3933.2011.01040.x https://doi.org/10.1111/j.1745-3933.2011.01040.x
- deleted 2y ago[deleted]