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arXiv · 1412.5473

The \'Etale Fundamental Groupoid as a Terminal Costack

Ilia Pirashvili
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Abstract

Let $X$ be a noetherian scheme. We denote by $\Pi_1(X)$ the fundamental groupoid. In this paper we prove that the assignments $U\mapsto\Pi_1(U)$ is the 2-terminal costack over the site of \'etale coverings of $X$.

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Ilia Pirashvili. 2014-12-17. The \'Etale Fundamental Groupoid as a Terminal Costack. https://doi.org/10.1215/21562261-2017-0041

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