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arXiv · 0707.0970

Non-abelian free groups admit non-essentially free actions on rooted trees

Miklos Abert·Gabor Elek
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Abstract

We show that every countable non-abelian free group $Γ$ admits a spherically transitive action on a rooted tree $T$ such that the action of $Γ$ on the boundary of $T$ is not essentially free. This reproves a result of Bergeron and Gaboriau. The existence of such an action answers a question of Grigorchuk, Nekrashevich and Sushchanskii.

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BibTeXRIS

Miklos Abert, Gabor Elek. 2007-07-18. Non-abelian free groups admit non-essentially free actions on rooted trees. https://arxiv.org/abs/0707.0970

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