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Set theory and number of universes

If a set is just a collection of objects, then a universe could be called a set, right? Assuming the answer to this question is yes, then is it even possible to have a universe containing all universes (assuming multiple universes)? I don't think it's possible because according to set theory, there can be no set that contains all sets (Russell's paradox). Then, what does this imply about the number of universes that there could possibly be?

Note by Hobart Pao
4 months, 1 week ago

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Nothing. The question is incoherent. A universe is not ""something"". It is the Totality of Everything. And the Totality of Everything is only one. More than One Totality is a contradiction. DarkMind S. · 4 months, 1 week ago

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@DarkMind S. What do you mean by "totality"? What about having multiple universes? Hobart Pao · 4 months ago

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Remember also that "Uni Verse or one turning" is a misnomer referring to the heliocentric view that the sun was the center of EVERYTHING (see Newman's Idea of a University) Soooo, if one uses the word KOSMOS meaning the totality of everything, I agree with DarkMind that "more than one totality" is a contradiction in terminology and perhaps also in reality. Jim Farley Santa Fe, New Mexico The question of odd or even is perhaps a bit metaphysical even for cosmology!! James Farley · 4 months, 1 week ago

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Darkmind, once you have a totality of everything, you cannot have something outside of it. Just because you find a separate universe somewhere doesn't mean it wasn't already in the set. If the set is defined as the "totality of everything" than nothing can be outside of it; the idea that it was outside is one of subjective perception, not of the function of the set. Right?

(Of course, I'm not as smart as most of you, so I could be wrong.) Peter Leinweber · 4 months ago

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There is no contradiction. The "thing" containing all universe is NOT a universe. (Call it 'multiverse' if you want). Hence, a multiverse need not contain itself. Eg : A plane can be set as the collection of all lines. But, it is still one plane and does not 'contain' any planes.

On the other hand, if you define universe as 'set of everything', there cannot be a second universe. Hence, there is only one set here. Janardhanan Sivaramakrishnan · 1 week, 5 days ago

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Nice solution Mainak Chaudhuri · 3 months ago

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