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A smooth counterexample to Nori's conjecture on the fundamental group scheme

Christian Pauly
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Abstract

We show that Nori's fundamental group scheme π(X,x) does not base change correctly under extension of the base field for certain smooth projective ordinary curves X of genus 2 defined over a field of characteristic 2.

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Christian Pauly. 2006-07-09. A smooth counterexample to Nori's conjecture on the fundamental group scheme. https://arxiv.org/abs/math/0607227

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