Constructible Sheaves

Madhav V. Nori

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arXiv · 1808.02417

Constructible Sheaves

Madhav V. Nori

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Abstract

This article contains a proof of the basic lemma. This lemma, discovered by Beilinson, yields a motivic proof of the Andreotti-Frankel theorem for affine varieties. Next, it is shown that the category of Cohomologically Constructible Sheaves (as it is referred to in the Riemann-Hilbert correspondence) coincides with the derived category of bounded complexes of constructible sheaves. It is also shown that higher direct images and the sheaf-Ext groups are effaceable in the category of constructible sheaves.

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Madhav V. Nori. 2018-08-07. Constructible Sheaves. https://arxiv.org/abs/1808.02417

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