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arXiv · 1404.7192

$\text{Gal}(\overline{\mathbf{Q}}_p/\mathbf{Q}_p)$ as a geometric fundamental group

Jared Weinstein
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Abstract

Let $p$ be a prime number. In this article we present a theorem, suggested by Peter Scholze, which states that the absolute Galois group of $\mathbf{Q}_p$ is the \'etale fundamental group of a certain object $Z$ which is defined over an algebraically closed field. Thus, local Galois representations correspond to local systems on $Z$. In brief, $Z$ is a (non-representable) quotient of a perfectoid space. The construction combines two themes: the fundamental curve of $p$-adic Hodge theory (due to Fargues-Fontaine) and the tilting equivalence (due to Scholze).

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Jared Weinstein. 2014-04-28. $\text{Gal}(\overline{\mathbf{Q}}_p/\mathbf{Q}_p)$ as a geometric fundamental group. https://arxiv.org/abs/1404.7192

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