Chennai Mathematical Institute


3:30-4:45 pm, Lecture Hall 1
Conormal Varieties on Cominuscule Grassmannians

Rahul Singh
Northeastern University, USA.


Consider a Schubert subvariety $X_w$ of a cominuscule Grassmannian $X$. In this talk, we construct a resolution of singularities, and for $X$ of type A,C, or D, also compute a system of defining equations, for the conormal variety of $X_w$ in $X$. The image of a conormal variety under the Springer map is an orbital variety. We will show how to use this to construct a resolution of singularities and a system of defining equations for certain orbital varieties in type A. Finally, time permitting, we will discuss current attempts at extending these results to general flag varieties. This talk is based on arXiv preprint 1805.12297.