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arXiv · 2003.04111

Coxeter quotients of the automorphism group of a Coxeter group

Olga Varghese
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Abstract

We show that for a large class $\mathcal{W}$ of Coxeter groups the following holds: Given a group $W_Γ$ in $\mathcal{W}$, the automorphism group ${\rm Aut}(W_Γ)$ virtually surjects onto some infinite Coxeter group. In particular, the group ${\rm Aut}(W_Γ)$ is virtually indicable and therefore does not have Kazhdan's property (T).

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Olga Varghese. 2022-09-01. Coxeter quotients of the automorphism group of a Coxeter group. https://arxiv.org/abs/2003.04111

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