Will Adkisson : Mutual Stationarity and Combinatorics at $\aleph_\omega$

Posted by Matthew Harrison-Trainor , part of the Logic Seminar.

At

Nov. 21, 2023, 4 p.m.

In

636 SEO

Abstract

Stationary sets are a fundamental concept in set theory, but their definition only makes sense at regular cardinals. We will describe mutual stationarity, a property that can be viewed as an analog of stationarity for singular cardinals, and discuss how it interacts with other combinatorial properties at or near $\aleph_\omega$. In particular, we will discuss stationary reflection and the failure of the Singular Cardinal Hypothesis.