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Symmetry between V and HOD
What is HYP? The minimal model?
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Stronger negation of AC given by rejecting "infinite hat" puzzles
It's Cartesian product. I'm splitting $X$ into two interleaved subsequences, which are in turn split into $|X|$ many $\omega$-sequences.
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Stronger negation of AC given by rejecting "infinite hat" puzzles
The variant in the linked post is slightly different. Rather than there being one box for every set of reals (i.e. the index set is $\mathcal{P}(\mathbb{R})$), I have the index set $X$ be the Hartogs number of $\mathbb{R}.$ I was just describing how to construct this set.
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Stronger negation of AC given by rejecting "infinite hat" puzzles
Is it strong enough to rule out the variant I describe in the second paragraph? My answer isn't about the standard 100 mathematician puzzle.
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Is $\in$-induction provable in first order Zermelo set theory?
@ZuhairAl-Johar That's right.
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Is $\in$-induction provable in first order Zermelo set theory?
@ZuhairAl-Johar Iterated power set.
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Is $\in$-induction provable in first order Zermelo set theory?
@DouglasUlrich That's a proper class in this model.
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Is $\in$-induction provable in first order Zermelo set theory?
@ZuhairAl-Johar Integers.
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Is $\in$-induction provable in first order Zermelo set theory?
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Is $\in$-induction provable in first order Zermelo set theory?
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Is $\in$-induction provable in first order Zermelo set theory?
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Do choice principles in all generic extensions imply AC in $V$?
And here I was debating whether to include AC$_{WO}$ in my list of choice principles at the beginning. Good to see this axiom put to use.
awarded
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Do choice principles in all generic extensions imply AC in $V$?
$X$ is the family of sets I want a choice function on, not $P(X).$
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Do choice principles in all generic extensions imply AC in $V$?
I mean set-generic but an answer for class-generic would be nice as well.
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Do choice principles in all generic extensions imply AC in $V$?
I am including trivial forcing. I don't see how that gives a positive answer. I'm only assuming the generic extensions (including $V$) satisfy weak choice principles.