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arXiv · 1610.02430

Local Euler obstructions of toric varieties

Bernt Ivar Utstøl Nødland
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Abstract

We use Matsui and Takeuchi's formula for toric A-discriminants to give algorithms for computing local Euler obstructions and dual degrees of toric surfaces and 3-folds. In particular, we consider weighted projective spaces. As an application we give counterexamples to a conjecture by Matsui and Takeuchi. As another application we recover the well-known fact that the only defective normal toric surfaces are cones.

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Bernt Ivar Utstøl Nødland. 2016-10-07. Local Euler obstructions of toric varieties. https://doi.org/10.1016/j.jpaa.2017.04.016

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