Everytopic Seminar

 October 16th, 2007, 1:40 pm – 3:00pm, Goldsmith 226

 

 

Title: Two conjectures, one false and one dubious

Speaker: Paul Monsky, Brandeis University

 

 

 

 

 

Abstract:

 

There are two fairly well-known conjectures in the theory of Hilbert-Kunz functions and tight closure:

(a)   Hilbert-Kunz multiplicities must be rational numbers;

(b)   Localization commutes with tight closure.

My talk will describe examples that refute (b) and make (a) seem very unlikely. The results on (a) arose from joint work with Teixeira; those on (b) are joint work with Brenner.