The Expanding Universe

I have to complete a deadline this morning, and we’re having visitors on a Monday afternoon. So I’m going to repost this blog about The Expanding universe from one of my favorite astrophysicists, Ethan Siegel. Ethan Siegel is a theoretical astrophysicist who currently teaches at the University of Portland in Portland, OR. You canlearn about him at that link. I enjoy reading his blog, because in contrast to Phil Plait, he posts more about astrophysics than any other topic (imagine that!).

Check out this entry.

Its bang starts like this:

Okay. Yesterday, I explained to you that the only thing that determines how the Universe expands is the amount of energy density in it. But many of you wanted more details. So, by popular demand — including one insistence that there is no equation that tells us how the Universe expands — here is the simplest explanation with math that I can come up with for the expanding Universe. If you hate or don’t care about math, do not read this. This article is not for you. But if you’re curious, read on.

Entry Here.