 Location
 UC Berkeley
 Video


 Abstract
 Commutative Algebra and Algebraic Geometry
Tuesdays, 3:456pm in Evans 939 Organizer: David Eisenbud http://hosted.msri.org/alg
Date: Tuesday, October 30
3:45 Srikanth Iyengar: Torsion in tensor powers of modules
The starting point of this talk is the observation that if a finitely generated module M over a noetherian (commutative!) domain R is NOT free, then its dfold tensorproduct has torsion for each d > rank_RM. In fact, when R is a regular local ring, torsion shows up already when d >= dim R; this is one of the central results in Auslander\\'s 1961 paper "Modules over unramified regular local rings". Recently Celikbas, Piepmeyer, R. Wiegand and I extended this result to certain modules over isolated hypersurface singularities; the preprint will be posted on the arXiv soon. My goal is to discuss some ideas that go into its proof. The main new tool is Hochster\\'s thetafunction, and is inspired by recent work of Dao.
5:00 Vu Thanh: Linear resolutions of powers of edge ideals of anticycles.
Let $I$ be the edge ideal of an anticycle of length at least $5$. We will show that all powers $I^k$, for $k \ge 2$ have linear resolution.
 Supplements


