Back to Algebraic Geometry Seminar: Fall 2016
Algebraic Geometry Seminar
Date: Tuesday, Sep 6, 2016
Time: 3:30PM - 4:30PM
Location: LCB 222
Chung Ching Lau
University of Utah
Title |
On subvarieties with nef normal bundle |
Abstract |
The goal of this talk is to study the positivity of subvarieties with nef normal bundle in terms of intersection theory. We first give a generalization to the notion of subvarieties with nef normal bundle, via the positivity of the exceptional divisor. We call these subvarieties nef. Then we show that restriction of a pseudoeffective divisor to a nef subvariety is pseudoeffective. We also show that nefness is a transitive property. Next, we define the weakly movable cone as the cone generated by the pushforward of cycle classes of nef subvarieties via proper surjective maps, and show that this cone contains the movable cone and shares similar intersection-theoretic properties with it, using the aforementioned properties of nef subvarieties. The main tool used in this work is the theory of $q$-ample divisors, as developed by Totaro. |
Algebraic Geometry