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arXiv · 2001.09506

The differential Galois group of the maximal prounipotent extension is free

Andy R. Magid
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Abstract

Let $F$ be a characteristic zero differential field with algebraically closed constant field, and consider the compositum $F_u$ of all Picard--Vessiot extensions of $F$ with unipotent differential Galois group. We prove that the group of $F$ differential automorphisms of $F_u$ is a free prounipotent group.

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Andy R. Magid. 2022-03-22. The differential Galois group of the maximal prounipotent extension is free. https://doi.org/10.1090/proc%2F15740

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