English

Separating Subversion Forcing Axioms

Logic 2025-08-06 v2

Abstract

We study a family of variants of Jensen's\emph{subcomplete forcing axiom}, SCFA\mathsf{SCFA} and \emph{subproper forcing axiom}, SubPFA\mathsf{SubPFA}. Using these we develop a general technique for proving non-implications of SCFA\mathsf{SCFA}, SubPFA\mathsf{SubPFA} and their relatives and give several applications. For instance we show that SCFA\mathsf{SCFA} does not imply MA+(σ\mathsf{MA}^+(\sigma-closed)) and SubPFA\mathsf{SubPFA} does not imply Martin's Maximum.

Keywords

Cite

@article{arxiv.2308.16276,
  title  = {Separating Subversion Forcing Axioms},
  author = {Hiroshi Sakai and Corey Bacal Switzer},
  journal= {arXiv preprint arXiv:2308.16276},
  year   = {2025}
}

Comments

19 pages, 1 figure, updated version addresses many helpful comments of the anonymous referee which helped clean up the text and clarify both the exposition and the proofs

R2 v1 2026-06-28T12:08:45.445Z