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arXiv · 1303.4079

Nori's Fundamental Group over a non Algebraically Closed Field

Lei Zhang
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Abstract

In this note we generalize Nori's definition of the fundamental group scheme from a rational point to an arbitrary base point so that when we take $X$ to be a field $k$ and the point to be $k\subseteq \bar{k}$ we still get a non trivial group scheme which is similar to the absolute Galois group ${\rm Gal}(\bar{k}/k)$. Then we try to understand the group scheme at various levels.

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Lei Zhang. 2013-03-17. Nori's Fundamental Group over a non Algebraically Closed Field. https://doi.org/10.2422/2036-2145.201604_007

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