English

Purity of generalized affine Springer fibers from generic planar curve singularities

Algebraic Geometry 2025-11-04 v2

Abstract

We prove the cohomological purity of punctual Hilbert schemes of points on generic irreducible planar curve singularities, by constructing an explicit affine paving. Via their identification with generalized GLNGL_N-affine Springer fibers attached to the direct sum of the adjoint and standard representations, this establishes a new case of the purity conjecture for generalized affine Springer fibers. The combinatorics of the paving - cell indices and dimensions - are controlled by (dn,dm)(dn,dm)-Dyck paths extending results of Gorsky-Mazin-Oblomkov on compactified Jacobians. As a byproduct, we also give a simpler proof of their bijection between admissible (dn,dm)(dn,dm)-invariant subsets and (dn,dm)(dn,dm)-Dyck paths.

Keywords

Cite

@article{arxiv.2509.20800,
  title  = {Purity of generalized affine Springer fibers from generic planar curve singularities},
  author = {Taiwang Deng and Tao Su},
  journal= {arXiv preprint arXiv:2509.20800},
  year   = {2025}
}

Comments

v2: 48 pages, 4 figures