Recent content by electronneutrino

Then why do we assume the current universe is homogeneous. I would expect inhomogeneous properties to be exacerbated not reduced

I just want to clarify my understanding of this statement about the big bang. If the universe is infinite and the big bang occurred everywhere, then the big bang constituted a universe with infinite mass energy in an infinite volume such that the mass density was finite and homogeneous as the...

So this would lead to a proper time of 0 seconds. ok that makes sense. Is it not also true that proper time can be interpreted as the time measured on a clock by an observer moving such that they are present at both events? In which case wouldn't such an observer measure the distance between...

I am refreshing myself on a bit of special relativity and I remember kind of taking the invariance of the spacetime interval for granted the first time. When thinking about it and running some examples I started to get confused so I decided to come here. All of the books I've read always have...