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arXiv · 0908.0498

On the homotopy exact sequence for Nori's fundamental group

Hélène Esnault·Phùng Hô Hai·Eckart Viehweg
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Abstract

Unlike Grothendieck's \'etale fundamental group, Nori's fundamental group does not fulfill the homotopy exact sequence in general. We give necessary and sufficient conditions which force exactness of the sequence.

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Hélène Esnault, Phùng Hô Hai, Eckart Viehweg. 2009-08-04. On the homotopy exact sequence for Nori's fundamental group. https://arxiv.org/abs/0908.0498

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