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arXiv · 1910.03563

Recovering function fields from their integral $\ell$-adic cohomology with the Galois action

Adam Topaz
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Abstract

In this note, we consider function fields of higher-dimensional algebraic varieties defined over non-local fields, and show how the Galois action on the cohomology such function fields can be used to parameterize their divisorial valuations. By applying a recent theorem of Pop, we observe that, in dimension $\geq 3$, this information is enough to completely determine the function field and the base-field in question.

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Adam Topaz. 2019-10-08. Recovering function fields from their integral $\ell$-adic cohomology with the Galois action. https://arxiv.org/abs/1910.03563

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