I've been trying to understand some basic stuff about cosmology for years, and I still can't quite get there. I'm not even sure which part of it I'm misunderstanding, and don't know what questions to ask, so I'll just start blasting out the questions and see if anyone can help me make sense out of it. So, first question has to do with geometry and topology I think, but I'm not sure how. Let's say that I can stop time completely right now, and I travel four billion light years in a straight line, in any direction (please, don't confuse me by asking me what I mean by "straight line"). Can anyone help me to understand what significant differences I'd see in the sky? Obviously different stars, but what I'm trying to get a handle on is this idea that nowhere is the center, but the universe isn't infinite. I understand the "open/flat/closed" geometry issue, or at least I think I do. I've heard our closed, finite space made analogous to the surface of a sphere. But I've also heard cosmologists assert that our universe is as flat as we can measure, so the sphere analogy doesn't work, I think. It seems to me that if I went four billion light years in some direction, I'd perceive that I'm getting close to the "edge" of something, that I'd see less in some direction: fewer galaxies? Ok, that's enough of a dumb question for now. If I can make sense out of that one, maybe I'll know what question to ask next. Twofish-quant, feel free to wait on answering until everyone else has weighed in. When I read your responses before everyone else's, my head explodes, and then there's a mess, and my mom gets mad.