$\mathbf {\Sigma }_1$ -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...

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Bibliographic Details
Main Authors: Philipp Lücke, Sandra Müller
Format: Article
Language:English
Published: Cambridge University Press 2023-01-01
Series:Forum of Mathematics, Sigma
Subjects:
Online Access:https://www.cambridge.org/core/product/identifier/S2050509423001020/type/journal_article