Open Colorings and Baumgartner's Axiom

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Authors: Lorenzo Notaro
Cited by: 0

Abstract

We construct a model of $\mathsf{MA_{\aleph_1}}+\mathsf{OCA}_T$ where Baumgartner's Axiom fails, settling a question of Farah. Moreover, in the same model there is an $\aleph_1$-dense set of reals which is neither reversible nor increasing, answering a question of Marun, Shelah, and Switzer.

Fields of Study & Subjects

Advanced Topology and Set Theory Computability Logic AI Algorithms Advanced Banach Space Theory

Publication details

Journal / source
arXiv (Cornell University)
Publication date
3 January 2026
Document type
Preprint