$\mathbf {\Sigma }_1$ -definability at higher cardinals: Thin sets, almost disjoint families and long well-orders
Given an uncountable cardinal $\kappa $ , we consider the question of whether subsets of the power set of $\kappa $ that are usually constructed with the help of the axiom of choice are definable by $\Sigma _1$ -formulas that only use the cardinal $\kappa $ and sets of here...
Main Authors: | , |
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Format: | Article |
Language: | English |
Published: |
Cambridge University Press
2023-01-01
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Series: | Forum of Mathematics, Sigma |
Subjects: | |
Online Access: | https://www.cambridge.org/core/product/identifier/S2050509423001020/type/journal_article |