Back to Algebraic Geometry Seminar: Fall 2013
Algebraic Geometry Seminar
Date: Thursday, Dec 5, 2013
Time: 3:30PM - 4:30PM
Location: LCB 225
(Thursday) Time/Location: 2:30pm/ JTB 140
Bhargav Bhatt
IAS
Title |
The proetale topology |
Abstract |
(joint work with Peter Scholze) The proetale topology is a Grothendieck topology that is closely related to the etale topology, yet better suited for certain “infinite” constructions, typically encountered in l-adic cohomology. I will first explain the basic definitions, with ample motivation, and then discuss applications. In particular, we will see why locally constant sheaves in this topology yield a fundamental group that is rich enough to detect all l-adic local systems through its representation theory (which fails for the groups constructed in SGA on the simplest non-normal varieties, such as nodal curves). |
Algebraic Geometry