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A comment on Observable Universe contains 10x more galaxies than previously thought (2016). Parent comment

Re:Observable Universe contains 10x more galaxies than previ... by SideburnsOfDoom on Thursday January 04, 2018 @06:50AM (#16069636)
My understanding is that the infinity of "all integers greater than zero" and of "all integers greater than zero and divisible by 2" are in fact infinities of the _same_ size.

The same would apply for "divisible by 100" or "divisible by 1 million". This would apply to the fraction of worlds that are populated, whatever fraction of them are.

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Re:Observable Universe contains 10x more galaxies than previ... by zimpenfish on Thursday January 04, 2018 @07:02AM (#16069696)
As best I understand it, all those reduce to aleph-zero because they're countably infinite and can be mapped to the natural numbers. But aleph-one exists and is provably bigger than aleph-zero despite both being infinite.

https://en.wikipedia.org/wiki/Aleph_number http://www.alephzero.co.uk/what.htm

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