The Decomposition Theorem and the topology of algebraic maps

Mark Andrea de Cataldo; Luca Migliorini

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arXiv · 0712.0349

The Decomposition Theorem and the topology of algebraic maps

Mark Andrea de Cataldo·Luca Migliorini

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Abstract

We give a motivated introduction to the theory of perverse sheaves, culminating in the Decomposition Theorem of Beilinson, Bernstein, Deligne and Gabber. A goal of this survey is to show how the theory develops naturally from classical constructions used in the study of topological properties of algebraic varieties. While most proofs are omitted, we discuss several approaches to the Decomposition Theorem, indicate some important applications and examples.

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Mark Andrea de Cataldo, Luca Migliorini. 2009-04-16. The Decomposition Theorem and the topology of algebraic maps. https://arxiv.org/abs/0712.0349

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