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arXiv · 1202.4732

Kummer Theory for Drinfeld Modules

Richard Pink
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Abstract

Let ϕ be a Drinfeld A-module of characteristic p0 over a finitely generated field K. Previous articles determined the image of the absolute Galois group of K up to commensurability in its action on all prime-to-p0 torsion points of ϕ, or equivalently, on the prime-to-p0 adelic Tate module of ϕ. In this article we consider in addition a finitely generated torsion free A-submodule M of K for the action of A through ϕ. We determine the image of the absolute Galois group of K up to commensurability in its action on the prime-to-p0 division hull of M, or equivalently, on the extended prime-to-p0 adelic Tate module associated to ϕ and M.

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Richard Pink. 2012-02-21. Kummer Theory for Drinfeld Modules. https://doi.org/10.2140/ant.2016.10.215

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