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KUMMER COVERINGS AND SPECIALISATION

Part of: Families, fibrations Algebraic geometry: Foundations

Published online by Cambridge University Press:  01 March 2021

Martin Olsson Open the ORCID record for Martin Olsson [Opens in a new window]
Martin Olsson*
Affiliation:
University of California, Berkeley, California, United States
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Abstract

We prove versions of various classical results on specialisation of fundamental groups in the context of log schemes in the sense of Fontaine and Illusie, generalising earlier results of Hoshi, Lepage and Orgogozo. The key technical result relates the category of finite Kummer étale covers of an fs log scheme over a complete Noetherian local ring to the Kummer étale coverings of its reduction.

Keywords

log geometryfundamental groupstacks

MSC classification

Primary: 14A20: Generalizations (algebraic spaces, stacks) 14D06: Fibrations, degenerations
Type
Research Article
Information
Journal of the Institute of Mathematics of Jussieu , Volume 21 , Issue 3 , May 2022 , pp. 1029 - 1065
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Copyright
© The Author(s), 2021. Published by Cambridge University Press

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