English

The Galvin property under the Ultrapower Axiom

Logic 2025-12-10 v4

Abstract

We continue the study of the Galvin property from \cite{bgs} and \cite{Benhamou2}. In particular, we deepen the connection between certain diamond-like principles and non-Galvin ultrafilters. We also show that any Dodd sound non p-point ultrafilter is non-Galvin. We use these ideas to formulate what appears to be the optimal large cardinal hypothesis implying the existence of a non-Galvin ultrafilter, improving on a result from \cite{Benhamou_Dobrinen}. Finally, we use a strengthening of the Ultrapower Axiom to prove that in all the known canonical inner models, a κ\kappa-complete ultrafilter has the Galvin property if and only if it is an iterated sum of pp-points.

Keywords

Cite

@article{arxiv.2306.15078,
  title  = {The Galvin property under the Ultrapower Axiom},
  author = {Tom Benhamou and Gabriel Goldberg},
  journal= {arXiv preprint arXiv:2306.15078},
  year   = {2025}
}

Comments

Added references and attributions, reorganized the proof of the main theorem, no new ideas