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arXiv · 1811.08251

The maximal discrete extension of $SL_2(\mathcal{\scriptstyle{O}}_K)$ for an imaginary-quadratic number field $K$

Aloys Krieg·Joana Rodriguez·Annalena Wernz
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Abstract

Let $\mathcal{\scriptstyle{O}}_K$ be the ring of integers of an imaginary quadratic number field $K$. In this paper we give a new description of the maximal discrete extension of the group $SL_2(\mathcal{\scriptstyle{O}}_K)$ inside $SL_2(\mathbb{C})$, which uses generalized Atkin-Lehner involutions. Moreover we find a natural characterization of this group in $SO(1,3)$.

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Aloys Krieg, Joana Rodriguez, Annalena Wernz. 2018-11-20. The maximal discrete extension of $SL_2(\mathcal{\scriptstyle{O}}_K)$ for an imaginary-quadratic number field $K$. https://arxiv.org/abs/1811.08251

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