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Automorphism groups of Coxeter groups do not have Kazhdans property (T)

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 Added by Olga Varghese
 Publication date 2020
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and research's language is English
 Authors Olga Varghese




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We show that for a large class $mathcal{W}$ of Coxeter groups the following holds: Given a group $W_Gamma$ in $mathcal{W}$, the automorphism group ${rm Aut}(W_Gamma)$ virtually surjects onto $W_Gamma$. In particular, the group ${rm Aut}(G_Gamma)$ is virtually indicable and therefore does not satisfy Kazhdans property (T). Moreover, if $W_Gamma$ is not virtually abelian, then the group ${rm Aut}(W_Gamma)$ is large.



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