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arXiv · 2509.04613

Hyperfiniteness of the boundary action of virtually special groups

Koichi Oyakawa
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Abstract

We prove that for any countable group acting virtually specially on a CAT(0) cube complex, the orbit equivalence relation induced by its action on the Roller boundary is hyperfinite. This can be considered as a generalization of hyperfiniteness of the boundary action of cubulated hyperbolic groups by Huang-Sabok-Shinko.

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BibTeXRIS

Koichi Oyakawa. 2025-09-04. Hyperfiniteness of the boundary action of virtually special groups. https://arxiv.org/abs/2509.04613

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