Abstract
By definition, a group is called narrow if it does not contain a copy of a non-abelian free group. We describe the structure of finite and narrow normal subgroups in Coxeter groups and their automorphism groups.
Funding source: Agence Nationale de la Recherche
Award Identifier / Grant number: ANR-19-CE40-0001-01
Funding source: Deutsche Forschungsgemeinschaft
Award Identifier / Grant number: VA 1397/2-2
Funding statement: The first author is supported by the French project “AlMaRe” (ANR-19-CE40-0001-01) of the ANR. The second author is supported by DFG grant VA 1397/2-2.
Acknowledgements
We want to thank Philip Möller for useful comments on the previous version of this paper and the referee for many helpful remarks.
Communicated by: Adrian Ioana
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