English

Hodge-Riemann polynomials

Algebraic Geometry 2025-11-07 v5 Combinatorics

Abstract

We show that Schur classes of ample vector bundles on smooth projective varieties satisfy Hodge-Riemann relations on Hp,qH^{p,q} under the assumption that Hp2,q2H^{p-2,q-2} vanishes. More generally, we study Hodge-Riemann polynomials, which are partially symmetric polynomials that produce cohomology classes satisfying the Hodge-Riemann property when evaluated at Chern roots of ample vector bundles. In the case of line bundles and in bidegree (1,1)(1,1), these are precisely the nonzero dually Lorentzian polynomials. We prove various properties of Hodge-Riemann polynomials, confirming predictions and answering questions of Ross and Toma. As an application, we show that the derivative sequence of any product of Schur polynomials is Schur log-concave, confirming conjectures of Ross and Wu.

Keywords

Cite

@article{arxiv.2506.16992,
  title  = {Hodge-Riemann polynomials},
  author = {Qing Lu and Weizhe Zheng},
  journal= {arXiv preprint arXiv:2506.16992},
  year   = {2025}
}

Comments

46 pages; v5: added a couple of examples

R2 v1 2026-07-01T03:26:37.249Z