malithion2 wrote:
twoshots wrote:
malithion2 wrote:
twoshots wrote:
chever wrote:
twoshots wrote:
If this is ambiguous, I am trying to say the universe can in fact be both infinite and expanding.
This makes no sense
How so? The universe's expansion isn't "expansion" in the way that a balloon expands. Wikipedia puts it concisely as
Quote:
Even if the overall spatial extent is infinite we still say that space is expanding, because locally the characteristic distance between objects is increasing.
And this is consistent with what else I have heard on the subject,
Put two dots on a balloon and you'll see the distance between them expand, this is basically the same thing minus a dimension. Infinite space would imply infinite space at the beginning of the universe: this is not true with the big bang considered all energy and space began at this finite event. Space in every sense could be infinite in a finite universe.
I really don't think the big bang refutes the possibility of infinite space. I'm not too up on the model, but I've heard enough cosmologists entertain the possibility without qualifications that the universe is infinite that it seems pretty clear that the big bang is not generally thought of as being evidence of such. How exactly that would work I do not understand as yet.
Well the big bang produced the first light in gamma radiation which has now red shifted to microwave radiation with this we can infer a time scale of about 14 billion years. With this we can assume the universe at the most basic is 14 billion light years in volume. At least that my thoughts on the subject.
Well, that ignores that the inflationary phase of expansion may have exceeded the speed of light (space can expand at whatever speed it wants too), and on top of that, oddly, wikipedia claims that the universe is actually much larger than that. One of their sources is
Constraining the Topology of the Universe, which says:
Quote:
For a wide class of models, the nondetection rules out the possibility that we live in a universe with topology scale smaller than 24 Gpc.
where Gpc is billions of parsecs.
This has something to do with the fact the univere's expansion or something. For example, I would suspect that although we may be seeing light emitted 14 billion years ago, what emitted that light has since had
plenty of time to get much farther away than that. Although I'm not sure if that is the correct explanation.
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* here for the nachos.