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arXiv · 2304.08399

Dually Lorentzian Polynomials

Julius Ross·Hendrik Süß·Thomas Wannerer
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Abstract

We introduce and study a notion of dually Lorentzian polynomials, and show that if $s$ is non-zero and dually Lorentzian then the operator \[s(\partial_{x_1},\ldots,\partial_{x_n}):\mathbb R[x_1,\ldots,x_n] \to \mathbb R[x_1,\ldots,x_n]\] preserves (strictly) Lorentzian polynomials. From this we conclude that any theory that admits a mixed Alexandrov-Fenchel inequality also admits a generalized Alexandrov-Fenchel inequality involving dually Lorentzian polynomials. As such we deduce generalized Alexandrov-Fenchel inequalities for mixed discriminants, for integrals of K\"ahler classes, for mixed volumes, and in the theory of valuations.

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Julius Ross, Hendrik Süß, Thomas Wannerer. 2023-04-17. Dually Lorentzian Polynomials. https://arxiv.org/abs/2304.08399

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