On copies of the absolute Galois group in $\operatorname {Out}\hat {F}_2$
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- by Robert A. Kucharczyk
- Proc. Amer. Math. Soc. 144 (2016), 2351-2359
- DOI: https://doi.org/10.1090/proc/12917
- Published electronically: October 20, 2015
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Abstract:
In this article we consider outer Galois actions on a free profinite group of rank two, induced by the étale fundamental group of a projective line minus three points or of a pointed elliptic curve over a number field. Under mild technical assumptions their respective images uniquely determine the curves and the number fields.References
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Bibliographic Information
- Robert A. Kucharczyk
- Affiliation: Mathematisches Institut, Universität Bonn, Endenicher Allee 60, 53115 Bonn, Germany—and—Departement Mathematik, ETH Zürich, Rämistrasse 101, 8092 Zürich, Switzerland
- Email: robert.kucharczyk@math.ethz.ch
- Received by editor(s): November 20, 2014
- Received by editor(s) in revised form: July 18, 2015
- Published electronically: October 20, 2015
- Additional Notes: This research was supported by the European Research Council
- Communicated by: Romyar T. Sharifi
- © Copyright 2015 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 144 (2016), 2351-2359
- MSC (2010): Primary 11G05, 11G32, 11R32, 14G25
- DOI: https://doi.org/10.1090/proc/12917
- MathSciNet review: 3477052