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arXiv · 2603.26501

Local-global principles for the existence of Levi factors

David Harbater·Julia Hartmann·George McNinch
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Abstract

We discuss local-global principles for the existence of Levi factors (i.e., complements to the unipotent radical) for linear algebraic groups over one-variable function fields. We give examples of disconnected groups that fail the local-global principle, and prove a strong local-global principle in the presence of Levi descent.

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David Harbater, Julia Hartmann, George McNinch. 2026-03-27. Local-global principles for the existence of Levi factors. https://arxiv.org/abs/2603.26501

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