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arXiv · 1301.0872

Unstable operations in étale and motivic cohomology

Bertrand Guillou·Charles Weibel
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Abstract

We classify all étale cohomology operations on $H_\et^n(-,\muell{i})$, showing that they were all constructed by Epstein. We also construct operations $P^a$ on the mod-$\ell$ motivic cohomology groups $H^{p,q}$, differing from Voevodsky's operations; we use them to classify all motivic cohomology operations on $H^{p,1}$ and $H^{1,q}$ and suggest a general classification.

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Bertrand Guillou, Charles Weibel. 2013-01-05. Unstable operations in étale and motivic cohomology. https://arxiv.org/abs/1301.0872

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