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Three point covers with bad reduction


Author: Stefan Wewers
Journal: J. Amer. Math. Soc. 16 (2003), 991-1032
MSC (2000): Primary 14H30, 11G20
DOI: https://doi.org/10.1090/S0894-0347-03-00435-1
Published electronically: July 8, 2003
MathSciNet review: 1992833
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Abstract: We study Galois covers of the projective line branched at three points with bad reduction to characteristic $p$, under the condition that $p$ strictly divides the order of the Galois group. As an application of our results, we prove that the field of moduli of such a cover is at most tamely ramified at $p$.


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Additional Information

Stefan Wewers
Affiliation: Mathematisches Institut, Beringstr. 1, 53115 Bonn, Germany
Email: wewers@math.uni-bonn.de

DOI: https://doi.org/10.1090/S0894-0347-03-00435-1
Keywords: Three point cover, stable reduction, field of moduli
Received by editor(s): January 10, 2003
Published electronically: July 8, 2003
Article copyright: © Copyright 2003 American Mathematical Society

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