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arXiv · 2304.03252

On the signature of unimodular fans

Paul Bressler·Diego A. Robayo Bargans
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Abstract

N.C.Leung and V.Reiner showed that certain convexity conditions on a complete rational simplicial fan determine the sign of the signature of the Poincar\'e pairing on the cohomology of the associated toric variety. The purpose of the present article is to give an "elementary" proof of their result.

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Paul Bressler, Diego A. Robayo Bargans. 2023-04-06. On the signature of unimodular fans. https://arxiv.org/abs/2304.03252

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