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arXiv · 2112.11293

The Hilbert Modular Group and Orthogonal Groups

Adrian Hauffe-Waschbüsch·Aloys Krieg
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Abstract

We derive an explicit isomorphism between the Hilbert modular group and certain congruence subgroups on the one hand and particular subgroups of the special orthogonal group $SO(2, 2)$ on the other hand. The proof is based on an application of linear algebra adapted to number theoretical needs.

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Adrian Hauffe-Waschbüsch, Aloys Krieg. 2021-12-21. The Hilbert Modular Group and Orthogonal Groups. https://arxiv.org/abs/2112.11293

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