Bott-Samelson varieties and combinatorics
Presenter
October 13, 2017
Keywords:
- Bott-Samelson variety
- associahedron
- rhombic tilings
- moment polytope
MSC:
- 14M15
- 52Bxx
Abstract
Schubert varieties parametrize families of linear spaces intersecting certain hyperplanes of C^n in a predetermined way. In the 1970’s Hansen and Demazure independently constructed resolutions of singularities for Schubert varieties: the Bott-Samelson varieties. In this talk I will describe their relation with associahedra. I will also discuss joint work with Pechenick-Tenner-Yong linking Magyar’s construction of these varieties as configuration spaces with Elnitsky’s rhombic tilings. Finally, based on joint work with Wyser-Yong, I will give a parallel for the Barbasch-Evens desingularizations of certain families of linear spaces which are constructed using symmetric subgroups of the general linear group.