What actually IS a universe?

[Guest]

Rather reluctantly, I have come to the conclusion that at least one of the multiverse theory versions is true.

 

BUT...

 

How do we define what a universe is? If you think it is the present of the universe we are in, then there is reason to suspect that all possible pasts, presents and futures exist simultaneously. So this definition of universe means that there are different versions of our universe. If all possible futures result in the end of the universe, then the number of versions is finite. If at least one future scenario (such as the rate of expansion slowing down and approaching but not quite reaching zero) then the number of versions is infinite. Perhaps this is what Stephen Hawking meant when he said that the universe is "infinite". I certainly DO NOT think that the universe is infinite in a spatial sense.

 

So the question is "is a universe just the here and now of our own reality or all possible pasts, presents and futures"?

 

Not exactly rocket science but many of us believe that the conditions of the early universe were similar to those of a black hole. Whether all black holes have expanded into other dimensions or each black hole has the ABILITY or POTENTIAL to expand into other dimensions is a moot point.

 

Some fanciful multiverse theories consider that you could pass through a block hole into another universe and that this universe is another past, present or future of our own. It is my opinion that each universe created from a black hole in our universe is totally independent of our universe and we can't go there, detect it or communicate with it. Not only that but all universes created from black holes are independent of each other and that their pasts, presents and futures exist.

 

So, depending on which definition you choose, we have a multiverse or a multimultiverse. However, in my opinion, the number of completely separate uni/multiverses that arise from black holes must be finite, although potentially very large. One of the questions is does every universe have the potential to create black holes?

[Tweedledee]

Fascinating and mind boggling stuff. ?

[Nightspore]