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arXiv · 1203.3022

A Lower Bound for the Exponent of Convergence of Normal Subgroups of Kleinian Groups

Johannes Jaerisch
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Abstract

We give a short new proof that for each non-elementary Kleinian group $\Gamma$, the exponent of convergence of an arbitrary non-trivial normal subgroup is bounded below by half of the exponent of convergence of $\Gamma$, and that strict inequality holds if $\Gamma$ is of divergence type.

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Johannes Jaerisch. 2012-03-14. A Lower Bound for the Exponent of Convergence of Normal Subgroups of Kleinian Groups. https://arxiv.org/abs/1203.3022

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