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arXiv · 2606.29107

On computation of unramified cohomology over non-closed fields

Wenhao Li
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Abstract

We give examples of varieties $X$ defined over a non-algebraically closed field $k$ with nontrivial unramified cohomology, in the case when the field $k$ is of bounded cohomological dimension, or the variety $X$ is a conic bundle over a rational surface and $k$ is an arbitrary field of characteristic different from $2$.

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Wenhao Li. 2026-06-27. On computation of unramified cohomology over non-closed fields. https://arxiv.org/abs/2606.29107

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