Algebra/Topology seminar

Speaker: Anders Buch

Title: Puzzles, Gromov-Witten invariants, and equivariant cohomology of 
two-step flag varieties

Abstract: I will speak about a proof of my conjectured puzzle formula for the 
equivariant Schubert structure constants of two-step flag varieties. 
This formula generalizes Knutson and Tao's puzzle rule for the 
equivariant cohomology of Grassmannians, as well as the cohomological 
puzzle rule for two-step flag varieties that was originally conjectured 
by Knutson.  Thanks to the equivariant version of the `quantum equals 
classical' result, my formula specializes to a Littlewood-Richardson 
rule for the equivariant quantum cohomology of Grassmannians.