English

On configurations concerning cardinal characteristics at regular cardinals

Logic 2021-02-02 v2 Combinatorics

Abstract

We study the consistency and consistency strength of various configurations concerning the cardinal characteristics sθ,pθ,gθ,rθ,tθ\mathfrak{s}_\theta,\mathfrak{p}_\theta,\mathfrak{g}_\theta,\mathfrak{r}_\theta,\mathfrak{t}_\theta at uncountable regular cardinals θ\theta. Motivated by a theorem of Raghavan-Shelah who proved that sθbθ\mathfrak{s}_\theta\leq\mathfrak{b}_\theta, we explore in the first part of the paper the consistency of inequalities comparing sθ\mathfrak{s}_\theta with pθ\mathfrak{p}_\theta and gθ\mathfrak{g}_\theta. In the second part of the paper we study variations of the extender-based Radin forcing to establish several consistency results concerning rθ\mathfrak{r}_\theta from hyper-measurability assumptions, results which were previously known to be consistent only from supercompactness assumptions. In doing so, we answer several questions which appeared in the literature.

Keywords

Cite

@article{arxiv.1905.06067,
  title  = {On configurations concerning cardinal characteristics at regular cardinals},
  author = {Omer Ben-Neria and Shimon Garti},
  journal= {arXiv preprint arXiv:1905.06067},
  year   = {2021}
}

Comments

25 pages, to appear