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arXiv · 2012.02853

A categorical K\"unneth formula for constructible Weil sheaves

Tamir Hemo·Timo Richarz·Jakob Scholbach
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Abstract

We prove a K\"unneth-type equivalence of derived categories of lisse and constructible Weil sheaves on schemes in characteristic $p > 0$ for various coefficients, including finite discrete rings, algebraic field extensions $E \supset \mathbf Q_\ell$, $\ell \ne p$ and their rings of integers $O_E$. We also consider a variant for ind-construtible sheaves which applies to the cohomology of moduli stacks of shtukas over global function fields.

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Tamir Hemo, Timo Richarz, Jakob Scholbach. 2020-12-04. A categorical K\"unneth formula for constructible Weil sheaves. https://doi.org/10.2140/ant.2024.18.499

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