The cosmic microwave background that we observe uniformly around us is usually explained by assuming that our universe is the surface of a four dimensional sphere. That way the uniformity makes sense ...
Since the cosmological constant is not required to explain that the universe seem to be expanding, why do we have it? What other factors cause us to have that constant? Background: Without the ...
If I am right, we can see only those stars that lie within our cosmological horizon, and there may or may not be any stars beyond that. Given last 150 years of using telescopes, and since then our ...