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arXiv · 1612.00208

$F$-divided sheaves trivialized by dominant maps are essentially finite

Fabio Tonini·Lei Zhang
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Abstract

By a result of Biswas and Dos Santos, on a smooth and projective variety over an algebraically closed field, a vector bundle trivialized by a proper and surjective map is essentially finite, that is it corresponds to a representation of the Nori fundamental group scheme. In this paper we obtain similar results for non-proper non-smooth algebraic stacks over arbitrary fields of characteristic $p>0$. As by-product we have the following partial generalization of the Biswas-Dos Santos' result in positive characteristic: on a pseudo-proper and inflexible stack of finite type over $k$ a vector bundle which is trivialized by a proper and flat map is essentially finite.

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Fabio Tonini, Lei Zhang. 2017-01-01. $F$-divided sheaves trivialized by dominant maps are essentially finite. https://doi.org/10.1090/tran%2F7444

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