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arXiv · 1604.02725

Complexity volumes of splittable groups

Mihalis Sykiotis
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Abstract

Using graph of groups decompositions of finitely generated groups, we define Euler characteristic type invariants which are non-zero in many interesting classes of finitely presented, hyperbolic, limit and CSA groups, including elementarily free groups and one-ended torsion-free hyperbolic groups whose JSJ decomposition contains a maximal hanging Fuchsian vertex group.

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Mihalis Sykiotis. 2016-04-10. Complexity volumes of splittable groups. https://arxiv.org/abs/1604.02725

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