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arXiv · 1708.01215

The Tits alternative for finite rank median spaces

Elia Fioravanti
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Abstract

We prove a version of the Tits alternative for groups acting on complete, finite rank median spaces. This shows that group actions on finite rank median spaces are much more restricted than actions on general median spaces. Along the way, we extend to median spaces the Caprace-Sageev machinery and part of Hagen's theory of unidirectional boundary sets.

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Elia Fioravanti. 2018-11-08. The Tits alternative for finite rank median spaces. https://doi.org/10.4171/lem%2F64-1%2F2-4

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