Time:  12:30  13:30 
Room: 
Wean Hall 7201

Speaker: 
Bill Chen Department of Mathematics UCLA 
Title: 
Can every mutually stationary sequence be tightly stationary?

Abstract:  Mutual and tight stationarity are two notions of stationarity defined on certain products associated to a singular cardinal, introduced by Foreman and Magidor. Tight stationarity is closely related to the structure of scales at the singular cardinal, whereas mutual stationarity has a more mysterious, modeltheoretic character. In this talk, I will investigate the question of Cummings, Foreman, and Magidor of whether every mutually stationary sequence can be tightly stationary. The main result is a model where mutual and tight stationarity are distinct everywhere (joint with Itay Neeman). 