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arXiv · 2508.01075

Cyclic orders and actions of Leary--Minasyan groups on coarse $\mathrm{PD}(n)$ spaces

Abstract

We show that for $n \geq 3$, there are torsion-free CAT(0) groups with visual boundaries that embed into $S^n$ but which are not virtually the fundamental group of a compact aspherical $n+1$-manifold. The groups are the CAT(0) and not bi-automatic groups constructed previously by Leary and Minasyan. The obstruction comes from analyzing certain cyclic orders on the boundary of the Bass-Serre tree, in the same manner as Kapovich-Kleiner ruled out actions of Baumslag-Solitar groups on coarse $\mathrm{PD}(3)$ spaces.

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BibTeXRIS

Arka Banerjee, Kevin Schreve. 2025-08-01. Cyclic orders and actions of Leary--Minasyan groups on coarse $\mathrm{PD}(n)$ spaces. https://arxiv.org/abs/2508.01075

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