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arXiv · 2005.05885

The symmetries of the Outer space of a universal Coxeter group

Yassine Guerch
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Abstract

This paper studies the geometric rigidity of the universal Coxeter group of rank $n$, which is the free product $W_n$ of $n$ copies of $\mathbb{Z}/2\mathbb{Z}$. We prove that for $n\geq 4$ the group of symmetries of the spine of the Guirardel-Levitt outer space of $W_n$ is reduced to the outer automorphism group $\mathrm{Out}(W_n)$.

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Yassine Guerch. 2020-05-12. The symmetries of the Outer space of a universal Coxeter group. https://arxiv.org/abs/2005.05885

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