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arXiv · 1911.05595

Tame and strongly étale cohomology of curves

Katharina Hübner
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Abstract

For a curve $C$ over a perfect field $k$ of characteristic $p > 0$ we study the tame cohomology of $X = \textit{Spa}(C,k)$ introduced in arXiv:1801.04776. We prove that the tame cohomology groups of $X$ with $p$-torsion coefficients satisfy cohomological purity (which is not true in full generality for the étale cohomology). Using purity we show Poincaré duality for the tame cohomology of $X$ with $p$-torsion coefficients.

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Katharina Hübner. 2020-04-11. Tame and strongly étale cohomology of curves. https://arxiv.org/abs/1911.05595

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