# Algebraic Geometry Seminar

#### Deformations of Symplectic Singularities and the Orbit Method

**Speaker:**
Ivan Losev, Northeastern University

**Location:**
Warren Weaver Hall 201

**Date:**
Tuesday, April 4, 2017, 3:30 p.m.

**Synopsis:**

Symplectic singularities were introduced by Beauville in 2000. These are especially nice singular Poisson algebraic varieties that include symplectic quotient singularities and the normalizations of orbit closures in semisimple Lie algebras. Poisson deformations of conical symplectic singularities were studied by Namikawa who proved that they are classified by the points of a vector space. Recently I have proved that quantizations of a conical symplectic singularity are still classified by the points of the same vector spaces. I will explain these results and then apply them to establish a version of Kirillov's orbit method for semisimple Lie algebras.