Seminar on BBD, Spring 2017

This is the webpage of the student learning seminar on algebraic geometry at Columbia. The predecessor of this seminar is the Remynar, from which the template for this page is partially copied.

This semester's topic is the Decomposition Theorem of Beilinson-Bernstein-Deligne. The main reference is the survey article [dCM] below, though we will need to consult other references to fill in details. We will assume familiarity with algebraic geometry at the level of Hartshorne, along with some basics of derived categories and ├ętale cohomology.


Please e-mail the organizers if you'd like to receive notifications.

Organizers: Shizhang Li, Carl Lian.

Time and location: Tuesday 16:30-18:00 in Math 507

*in addition to the unusual dates, these talk will take place 10:00-11:30 in Math 528.

Date Speaker Title Ref.
17 Jan Shizhang Li Introduction [dCM] 1
24 Jan Qixiao Ma Six Functors; Verdier Duality [dCM] 5.3, 5.8
31 Jan Henry Liu Intersection Cohomology, I [dCM] 2.1-2.2
7 Feb Raymond Cheng Intersection Cohomology, II [dCM] 2.1-2.2
14 Feb Semon Rezchikov Perverse Sheaves, I [dCM] 2.3-2.5, [KW] 3
21 Feb Leonardo Lerer Perverse Sheaves, II [dCM] 2.3-2.5, [KW] 3
6 Mar* David Hansen Lefschetz Hyperplane Theorem, Intermediate Extensions [dCM] 2.6-2.7
7 Mar Dmitrii Pirozhkov Overview of Proof [dCM] 3.1
14 Mar No talk: Spring break/AWS
21 Mar Dan Gulotta Semismall Maps [dCM] 4.2
27 Mar* Noah Arbesfeld Gottsche's Formula
4 Apr Cancelled
11 Apr David Hansen Geometric Satake Isomorphism
18 Apr Daniel Litt The P=W Conjecture
25 Apr Shizhang Li On Bhatt-Schnell-Scholze