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arXiv · 2510.14571

Linearity criteria for automorphism groups of malabelian groups

Thomas Koberda·Mark Pengitore
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Abstract

Let $G$ be a finitely generated malabelian group, let $A\leq\mathrm{Out}(G)$ be a finitely generated subgroup, and let $\Gamma_{G,A}$ denote the preimage of $A$ in $\mathrm{Aut}(G)$. We give a general criterion for the linearity of $\Gamma_{G,A}$ in terms of surjections from $G$ to finite simple groups of Lie type.

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Thomas Koberda, Mark Pengitore. 2025-10-16. Linearity criteria for automorphism groups of malabelian groups. https://arxiv.org/abs/2510.14571

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