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Cosmonut
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  • Member for 9 years, 4 months
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Replacing Axiom of Choice with Axiom of Countable Choice
Very interesting. I am editing my question accordingly.
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Ordering of large cardinals by cardinality
Fantastic answer and a lot to digest. Thank you very much.
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Ordering of large cardinals by cardinality
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Wholeness Axiom and Ultimate L
Thanks Joel. Cantor's Attic is a great resource ! I modified my question in response to your comment.
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Wholeness Axiom and Ultimate L
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Why should we care about "higher infinities" outside of set theory?
Thanks a lot for the very comprehensive answer and links. I guess the answer to my question would be "The cardinality-challenged mathematician would get along just fine since a very large part of 'regular math' can be done with weaker versions of set theory without crazy multiplicities of uncountable cardinals" Large cardinal theory sounds very intriguing. Are there any good books at the advanced undergrad/beginning grad level I could learn it from ?
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Why should we care about "higher infinities" outside of set theory?
Terry: "To me, it's not so much that the multiplicity of uncountable cardinals comes up directly all that much in mathematics, but rather that they are inevitable byproducts of the very useful set theory axioms" Thanks ! That's very helpful.
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Why should we care about "higher infinities" outside of set theory?
Terry, I was coming at this from a different angle. For instance, suppose we did not have the Power Set Axiom. One could still prove that the reals had a higher cardinality than the naturals as in the link below for example. boolesrings.org/scoskey/my-favorite-proof-that-r-is-uncounta‌​ble Would there be any theorems outside of set theory - hence, not relying on the Power Set Axiom, perhaps - that would force us to conclude that some mathematical object had a cardinality higher than R ?