On copies of the absolute Galois group in 𝑂𝑢𝑡𝐹̂₂

Kucharczyk, Robert

doi:10.1090/proc/12917

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.

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