Intersection properties of stable subgroups and bounded cohomology

Yago Antolín; Mahan Mj; Alessandro Sisto; Samuel J. Taylor

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arXiv · 1612.07227

Intersection properties of stable subgroups and bounded cohomology

Yago Antolín·Mahan Mj·Alessandro Sisto·Samuel J. Taylor

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Abstract

We show that a finite collection of stable subgroups of a finitely generated group has finite height, finite width and bounded packing. We then use knowledge about intersections of conjugates to characterize finite families of quasimorphisms on hyperbolically embedded subgroups that can be to simultaneously extended to the ambient group.

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Yago Antolín, Mahan Mj, Alessandro Sisto, Samuel J. Taylor. 2016-12-21. Intersection properties of stable subgroups and bounded cohomology. https://arxiv.org/abs/1612.07227

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