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arXiv · 2408.02499

Motivic p-adic tame cohomology

Alberto Merici
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Abstract

We construct a comparison functor between ($\mathbf{A}^1$-local) tame motives and ($\overline{\square}$-local) log-\'etale motives over a field $k$ of positive characteristic. This generalizes Binda--Park--{\O}stv{\ae}r's comparison for the Nisnevich topology. As a consequence, we construct an $E_\infty$-ring spectrum $H\mathbb{Z}/p^m$ representing mod $p^m$ tame motivic cohomology: the existence of this ring spectrum and the usual properties of motives imply some results on tame motivic cohomology, which were conjectured by H\"ubner--Schmidt.

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Alberto Merici. 2024-08-05. Motivic p-adic tame cohomology. https://arxiv.org/abs/2408.02499

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