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arXiv · 2212.10261

Geometric condition for Dependent Choice

Asaf Karagila·Jonathan Schilhan
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Abstract

We provide a geometric condition which characterises when the Principle of Dependent Choice holds in a Fraenkel--Mostowski--Specker permutation model. This condition is a slight weakening of requiring the filter of groups to be closed under countable intersections. We show that this condition holds nontrivially in a new permutation model we call "the nowhere dense model" and we study its extensions to uncountable cardinals as well.

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Asaf Karagila, Jonathan Schilhan. 2022-12-20. Geometric condition for Dependent Choice. https://doi.org/10.1007/s10474-024-01396-0

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