On forcing axioms and weakenings of the Axiom of Choice

Diego Lima Bomfim; Charles Morgan; Samuel Gomes da Silva

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arXiv · 2404.10736

On forcing axioms and weakenings of the Axiom of Choice

Diego Lima Bomfim·Charles Morgan·Samuel Gomes da Silva

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Abstract

We prove forcing axiom equivalents of two families of weakenings of the axiom of choice: a trichotomy principle for cardinals isolated by L\'evy, ${\rm H\hskip0.05pt}_\kappa$, and ${\rm DC}_\kappa$, the principle of dependent choices generalized to cardinals $\kappa$, for regular cardinals $\kappa$. Using these equivalents we obtain new forcing axiom formulations of the axiom of choice. A point of interest is that we use a new template for forcing axioms. For the class of forcings to which we asks that the axioms apply, we do not ask that they apply to all collections of dense sets of a certain cardinality, but rather only for each particular forcing to a specific family of dense sets of the cardinality in question.

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BibTeX RIS

Diego Lima Bomfim, Charles Morgan, Samuel Gomes da Silva. 2024-04-16. On forcing axioms and weakenings of the Axiom of Choice. https://arxiv.org/abs/2404.10736

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