2017/10/15 by Oblomkov, Alexei, Yun, Zhiwei · 1 citation
#14F20 #14F40 #Algebraic Geometry (math.AG) #FOS: Mathematics
paper · doi:10.48550/arxiv.1710.05391
We provide an explicit presentation of the equivariant cohomology ring of the compactified Jacobian Jq/p of the rational curve Cq/p with planar equation xq=yp for (p,q)=1. We also prove analogous results for the closely related affine Springer fiber Spq/p in the affine flag variety of SLp. We show that the perverse filtration on the cohomology of Jq/p is multiplicative, and the associated graded ring under the perverse filtration is a degeneration of the ring of functions on a moduli space of maps ℙ1→ Cq/p. We also propose several conjectures about Jq/p and more general compactified Jacobians.