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arXiv · 2312.08505

On schemes with trivial higher étale homotopy groups

Mohammed Moutand
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Abstract

Let $(X,\bar x)$ be a pointed connected noetherian scheme. In this note, we give characterizations for the vanishing of the second étale homotopy group $π^{\rm ét}_2(X,\bar x)$ in terms of splitting profinite-étale covers of $X$, and by means of universal covering spaces of the Artin-Mazur-Friedlander étale homotopy type $Et(X)$. In particular, this provides certain classes of schemes for which the Brauer map is surjective.

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Mohammed Moutand. 2026-02-26. On schemes with trivial higher étale homotopy groups. https://arxiv.org/abs/2312.08505

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