Characteristic cycle and the Euler number of a constructible sheaf on a surface

Takeshi Saito

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arXiv · 1402.5720

Characteristic cycle and the Euler number of a constructible sheaf on a surface

Takeshi Saito

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Abstract

We define the characteristic cycle of a constructible sheaf on a smooth surface in the cotangent bundle. We prove that the intersection number with the 0-section equals the Euler number and that the total dimension of vanishing cycles at an isolated characteristic point is also computed as an intersection number.

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Takeshi Saito. 2014-02-24. Characteristic cycle and the Euler number of a constructible sheaf on a surface. https://arxiv.org/abs/1402.5720

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