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arXiv · 0908.2272

Commensurators of non-free finitely generated Kleinian groups

C. J. Leininger·D. D. Long·A. W. Reid
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Abstract

Suppose G is a non-free finitely generated Kleinian group without parabolics which is not a lattice and let C(G) denote the commensurator in PSL(2,C). We prove that if the limit set of G is not a round circle, then C(G) is discrete. Furthermore, G has finite index in C(G) unless G is a fiber group in which case C(G) is a lattice.

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C. J. Leininger, D. D. Long, A. W. Reid. 2009-08-17. Commensurators of non-free finitely generated Kleinian groups. https://doi.org/10.2140/agt.2011.11.605

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