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arXiv · 1708.08338

Brasselet number and Newton polygons

Thais M. Dalbelo·Luiz Hartmann
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Abstract

We present a formula to compute the Brasselet number of $f:(Y,0)\to (\C, 0)$ where $Y\subset X$ is a non-degenerate complete intersection in a toric variety $X$. As applications we establish several results concerning invariance of the Brasselet number for families of non-degenerate complete intersections. Moreover, when $(X,0) = (\mathbb{C}^n,0)$ we derive sufficient conditions to obtain the invariance of the Euler obstruction for families of complete intersections with an isolated singularity which are contained in $X$.

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Thais M. Dalbelo, Luiz Hartmann. 2017-08-24. Brasselet number and Newton polygons. https://arxiv.org/abs/1708.08338

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