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arXiv · 2603.11116

$\mathbb{R}$--trees and accessibility over arc-stabilisers

Elia Fioravanti
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Abstract

Let $G\curvearrowright T$ be a minimal action on an $\mathbb{R}$--tree with $G$ finitely presented. Assuming that $G$ is accessible over the family of arc-stabilisers of $T$, we give a description of the point-stabilisers of $T$ in terms of simplicial trees. In particular, these point-stabilisers are finitely generated. This has applications to the study of automorphisms of right-angled Artin groups and special groups.

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Elia Fioravanti. 2026-03-11. $\mathbb{R}$--trees and accessibility over arc-stabilisers. https://arxiv.org/abs/2603.11116

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