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arXiv · 1705.07017

Boundary amenability of $Out(F_N)$

Mladen Bestvina·Vincent Guirardel·Camille Horbez
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Abstract

We prove that $Out(F_N)$ is boundary amenable. This also holds more generally for $Out(G)$, where $G$ is either a toral relatively hyperbolic group or a finitely generated right-angled Artin group. As a consequence, all these groups satisfy the Novikov conjecture on higher signatures.

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Mladen Bestvina, Vincent Guirardel, Camille Horbez. 2017-05-19. Boundary amenability of $Out(F_N)$. https://arxiv.org/abs/1705.07017

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