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arXiv · 1604.02845

Chern-Mather classes of toric varieties

Ragni Piene
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Abstract

The purpose of this short note is to prove a formula for the Chern-Mather classes of a toric variety in terms of its orbits and the local Euler obstructions at general points of each orbit (Theorem 2). We use the general definition of the Chern-Schwartz-MacPherson classes (see [7]) and their special expression in case of a toric variety (see [2]). As a corollary, we obtain a formula by Matsui-Takeuchi [8, Corollary 1.6]. Alternatively, one could deduce the formula of Theorem 2 from the Matsui-Takeuchi formula, by using our general result [11, Theoreme 3] for the degree of the polar varieties in terms of the Chern-Mather classes.

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Ragni Piene. 2016-04-11. Chern-Mather classes of toric varieties. https://arxiv.org/abs/1604.02845

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