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arXiv · 2102.02553

Subgroups of free proalgebraic groups and Matzat's conjecture for function fields

Michael Wibmer
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Abstract

We show that a closed finite index subgroup of a free proalgebraic group is itself a free proalgebraic group. Our main motivation for this result is an application in differential Galois theory: The absolute differential Galois group of a one-variable function field is a free proalgebraic group.

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Michael Wibmer. 2021-02-04. Subgroups of free proalgebraic groups and Matzat's conjecture for function fields. https://arxiv.org/abs/2102.02553

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