English

Stabilization of intersection Betti numbers for moduli spaces of one-dimensional sheaves on surfaces

Algebraic Geometry 2026-02-11 v2

Abstract

In this paper, we develop a unified approach to study the intersection Betti numbers of moduli spaces of one-dimensional semistable sheaves on smooth projective surfaces. Assuming the irreducibility of such moduli spaces, we prove that their intersection Betti numbers in a certain range of degrees coincide with the stable Betti numbers of Hilbert schemes of points. As an application, for minimal surfaces of Kodaira dimension 0, we show that these intersection Betti numbers stabilize in each fixed degree, which fits into the broader context of stable cohomology for moduli spaces of sheaves. In the case of Enriques surfaces, we also prove a refined stabilization result related to Oberdieck's conjecture on perverse Hodge numbers.

Keywords

Cite

@article{arxiv.2511.18426,
  title  = {Stabilization of intersection Betti numbers for moduli spaces of one-dimensional sheaves on surfaces},
  author = {Fei Si and Feinuo Zhang},
  journal= {arXiv preprint arXiv:2511.18426},
  year   = {2026}
}

Comments

23 pages. v2: results strengthened, exposition improved. Comments are very welcome!