If the big bang occurs at the first moment of time, then how can there be a multiverse?
Well, basically, there was a beginning to our region of the universe, but that doesn't say anything about what exists beyond our region.
(1) The current big bang theory is supported by a mathematical analysis that breaks down if taken back to t=0, so we say that there IS no such think and t=0 or t<0 BUT ... that's just an artifact of the model. It is not absolutely proven that these things don't exist and there are other models that suggest, or even state, that they DO exist.
(2) To add to what Chalnoth said, we don't have definitive proof of anything outside our own observable universe in either time OR space. All else is conjecture. (It IS, I believe, very GOOD conjecture though)
So it's only the beginning of the space-time within the universe.
well I think the statement should be a bit stonger than that. It is the beginning of space-time in the universe AS WE KNOW it (and as our math models are able to describe it).
There is no proof that it is NOT the beginning of space-time PERIOD, so until we know otherwise ...
all of which statements are nonsensical on both ends. The first person saying there can be only one is wrong and the 2nd person saying there MUST be more than one is wrong. Had he said there MAY be more than one, THEN it would be logical.
The has been a post deletion, which makes my post #6 nonsensical. I would appreciate it if the moderators would add some comment when they remove a post.
Nervous....we live in a universe that supposedly started with a big bang. That doesnt mean that a new big bang within the "spaces in-between spaces" is occurring right now...and now...and now. As I type this, many different universes may be filling up with their own space and time. This is why many refer to everything collectively as a multiverse.
I think it's more accurate to term it "metaverse" personally, but to each their own.
In a very real way, the Big Bang represents a time where all the information about everything that we can see was condensed to a single point and normalized. We don't know anything about "before" that because all the information of it was normalized into something homogenous. It could be an absolute beginning, or it could not. We don't know, because that information was destroyed in the formation of the Universe we live in.
Well, it never was a single point. Our observable universe was contained in a very small, high-density, high-temperature region. But not infinitely-small.
Ah, but the math does not accept t = 0. :)
I didn't mean to state that as a fact. It is an interpretation of t = 0... that is, the singularity concept.
You're right though. So long as spacetime has existed, the Universe has not been a single point.
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