Hodge-Riemann polynomials

Abstract: We show that Schur classes of ample vector bundles on smooth projective varieties satisfy Hodge--Riemann relations on $H^{p,q}$ under the assumption that $H^{p-2,q-2}$ 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 $(1,1)$, 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 a product of Schur polynomials is Schur log-concave, confirming conjectures of Ross and Wu.