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arXiv · 2504.21802

Anosov representations of amalgams

Abstract

For uniform lattices $Γ$ in rank 1 Lie groups, we construct Anosov representations of virtual doubles of $Γ$ along certain quasiconvex subgroups. We also show that virtual HNN extensions of these lattices over some cyclic subgroups admit Anosov embeddings. In addition, we prove that for any Anosov subgroup $Γ$ of a real semisimple linear Lie group $\mathsf{G}$ and any infinite abelian subgroup $\mathrm{H} $ of $ Γ$, there exists a finite-index subgroup $Γ' $ of $ Γ$ containing $\mathrm{H}$ such that the double $Γ' *_{\mathrm{H}} Γ'$ admits an Anosov representation, thereby confirming a conjecture of [arXiv:2112.05574]. These results yield numerous examples of one-ended hyperbolic groups that do not admit discrete and faithful representations into rank 1 Lie groups but do admit Anosov embeddings into higher-rank Lie groups.

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BibTeXRIS

Subhadip Dey, Konstantinos Tsouvalas. 2025-04-30. Anosov representations of amalgams. https://arxiv.org/abs/2504.21802

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