Manureofhistory OP t1_j4g75j6 wrote on January 15, 2023 at 2:31 PM

Reply to comment by f_d in The multiverse by Manureofhistory

That’s interesting but I think the problem with the infinite is the issue of infinite regress, right? So are we thinking of infinite as a sort of shaped vacuity? That would be something like an infinite set, whatever that means. That raises big questions about what we mean when we say infinite.

f_d t1_j4jirnn wrote on January 16, 2023 at 3:49 AM

I'm not sure I follow you here at all. There doesn't have to be any problem with infinite. It's just something that goes on forever.

Things can also be infinite in one direction and finite in another. Our universe might have a finite start at its beginning leading into endless expansion into time and space.

Some infinities come to a virtual end without ever quite reaching it. Much of calculus depends on plugging in infinity to figure out the value an equation will eventually close in on.

Things that are infinite are not identical to each other. You can have a densely populated infinity or a sparsely populated infinity or an empty infinity. You can have a diverse infinity or a homogeneous one. You can have an infinity that is always larger or smaller than another infinity wherever you measure it.

The observable universe stretches equally in every direction without any sign it is approaching a boundary. It doesn't have universe-scale landmarks to set its regions apart from each other. On the largest scale, it meets all the requirements to be an infinitely large, infinitely growing environment with only superficial differences at smaller scales. So that's already one set of infinities in play before we introduce additional universes.

We don't know what rules apply outside our universe, so talking about what infinities are or are not possible with those rules doesn't mean anything either.