On Gehring-Martin-Tan groups with an elliptic generator

Andrei Yu. Vesnin; Dušan D. Repovš

doi:10.1017/s0004972716000228

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arXiv · 1609.05044

On Gehring-Martin-Tan groups with an elliptic generator

Andrei Yu. Vesnin·Dušan D. Repovš

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Abstract

The Gehring-Martin-Tan inequality for 2-generator subgroups of PSL(2,C) is one of the best known discreteness conditions. A Kleinian group $G$ is called a Gehring-Martin-Tan group if the equality holds for the group $G$. We give a method for constructing Gehring-Martin-Tan groups with a generator of order four and present some examples. These groups arise as groups of finite volume hyperbolic 3-orbifolds.

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BibTeX RIS

Andrei Yu. Vesnin, Dušan D. Repovš. 2016-09-16. On Gehring-Martin-Tan groups with an elliptic generator. https://doi.org/10.1017/s0004972716000228

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