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ALGEBRAIC AND NORI FUNDAMENTAL GERBES

Published online by Cambridge University Press:  07 July 2017

Fabio Tonini
Affiliation:
Freie Universität Berlin, FB Mathematik und Informatik, Arnimallee 3, Zimmer 112A, 14195 Berlin, Deutschland ([email protected]; [email protected])
Lei Zhang
Affiliation:
Freie Universität Berlin, FB Mathematik und Informatik, Arnimallee 3, Zimmer 112A, 14195 Berlin, Deutschland ([email protected]; [email protected])

Abstract

In this paper we extend the generalized algebraic fundamental group constructed in Esnault and Hogadi, (Trans. Amer. Math. Soc. 364(5) (2012), 2429–2442) to general fibered categories using the language of gerbes. As an application we obtain a Tannakian interpretation for the Nori fundamental gerbe defined in Borne and Vistoli (J. Algebraic Geom. (2014), S1056–3911, 00638-X) for nonsmooth non-pseudo-proper algebraic stacks.

Type
Research Article
Copyright
© Cambridge University Press 2017 

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Footnotes

This work was supported by the European Research Council (ERC) Advanced Grant 0419744101 and the Einstein Foundation.

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