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arXiv · 2204.04165

Cohomological and motivic inclusion-exclusion

Ronno Das·Sean Howe
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Abstract

We categorify the inclusion-exclusion principle for partially ordered topological spaces and schemes to a filtration on the derived category of sheaves. As a consequence, we obtain functorial spectral sequences that generalize the two spectral sequences of a stratified space and certain Vassiliev-type spectral sequences; we also obtain Euler characteristic analogs in the Grothendieck ring of varieties. As an application, we give an algebro-geometric proof of Vakil and Wood's homological stability conjecture for the space of smooth hypersurface sections of a smooth projective variety. In characteristic zero this conjecture was previously established by Aumonier via topological methods.

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Ronno Das, Sean Howe. 2022-04-08. Cohomological and motivic inclusion-exclusion. https://arxiv.org/abs/2204.04165

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