Nabla positivity and Tor groups

11.02.2020 13:15 - 14:45

Erik Carlsson (UC Davis)

I will describe some new formulas with A. Mellit for the nabla operator from Haiman-Garsia-Macdonald theory in two different modified elementary symmetric function bases. I will explain their geometric origin, and pose some new conjectures for which these formulas would be a corollary, that would imply the conjectured positivity of this operator in the Schur basis, and are also related to certain Tor groups studied by Goresky, Kottwitz, and Macpherson related to the affine Springer fiber in type A.

Organiser:

H. Grobner, A. Minguez-Espallargas, A. Mellit

Location:

BZ 2, 2. OG., OMP 1