School of Mathematics Seminars and Lectures

Semiorthogonal decompositions for singular varieties

by Evgeny Shinder (University of Sheffield)

Friday, October 23, 2020 from to (Asia/Kolkata)
at over zoom
Description
Abstract:
I will define a semiorthogonal decomposition for derived categories of
singular projective varieties due to Kawamata, into finite-dimensional
algebras, generalizing the concept of an exceptional collection in the
smooth case. I will present known constructions of these for nodal curves
(Burban), torsion-free toric surfaces (Karmazyn-Kuznetsov-Shinder) and two
nodal threefolds (Kawamata). Finally, I will explain obstructions coming
from the K_{-1} group, and how it translates to maximal nonfactoriality in
the nodal threefold case. This is joint work with M.Kalck and N.Pavic.