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arXiv · 2601.22514

Note on Euler characteristic of a toric vector bundle

Suhyon Chong·Shaoyu Huang·Kiumars Kaveh
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Abstract

A convex chain is a finite integer linear combination of indicator functions of convex polytopes. Khovanskii-Pukhlikov extend the Ehrhart theory of convex lattice polytopes to the setting of convex chains. Extending the relationship between equivariant line bundles on projective toric varieties and virtual lattice polytopes, we associate a lattice convex chain to a torus equivariant vector bundle on a toric variety and show that sum of values of this convex chain on lattice points gives the Euler characteristic of the bundle.

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Suhyon Chong, Shaoyu Huang, Kiumars Kaveh. 2026-01-30. Note on Euler characteristic of a toric vector bundle. https://arxiv.org/abs/2601.22514

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