Why is the universe so homogenous? It should be a lot more clumpy.
Right after the Big Bang, the universe was still quite small and all the matter was compressed in this small volume. So gravity should have played a big role, causing all the matter to clump together with large areas of empty space in between.
Decades ago, some theorists developed the “inflation” theory to explain this fact. They said that right after the big bang, the universe expanded super incredibly fast. So fast that gravity didn’t have time to clump the matter together. This is why matter is spread so evenly, like a thin layer of peanut butter over a slice of bread, throughout the visible universe.
Lots of scientists didn’t believe it. I was among them. This didn’t make any sense because the expansion rate would be so fast, in a way, faster than the speed of light. Couldn’t happen.
Well, now we have physical proof that inflation really did happen.
This is really amazing. I’m glad I was wrong — it is so much more interesting this way!