When I was in college there was an explanation of the expanding universe that resonated with me but did not fully compute in my mind. It wasn’t until recently when I saw a video that was saying the same thing, but with a slightly different visual, that it finally settled.
The consensus amongst scientists is that the universe is expanding at an accelerated rate. This part I got before but I wasn’t quite grasping it properly. It wasn’t that in this vast nothingness the galaxies were racing away from one another, this might be true but this wasn’t what my professor was trying to emphasize. It is that space itself was expanding at an accelerated rate.
The visual in college was raisin bread, you imagine that each raisin in the bread is a galaxy, space itself is the bread that the Raisins are in. When you first start baking they are all close together, however as the bread warms and begins to rise the physical space between the raisins actually stretches. The distance between the raisins grows. So it is not that the raisins have been fired from a cannon, but instead the foundation that they have settled into is itself growing.
It’s difficult for my brain to fully wrap around but interesting nonetheless. Furthermore what is neat is that because the universe is expanding in this way, there can be light that was formed at the beginning of the universe that still hasn’t reached other sources in the universe. While objects within the universe do not travel faster than light, the universe itself certainly can.
That, to me, is crazy interesting. Furthermore there is matter out there whose light has not yet reached the Earth in any way. This means that there is space out there that we’ve never seen in any fashion. A ring of darkness between us and eternity. I realize that chances are good it all looks very similar to everything within the darkness, but my curiosity is still peaked by the rest of the universe hiding outside our vision.
Might sound silly but I don’t think I can ever watch baking bread again without imagining the universe.