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arXiv · 2203.09853

Relating Siegel cusp forms to Siegel-Maa{\ss} forms

Jürg Kramer·Antareep Mandal
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Abstract

In this paper we generalize a well-known isomorphism between the space of cusp forms of weight $k$ for a Fuchsian subgroup of the first kind $\Gamma \subset\mathrm{SL}_{2}(\mathbb{R})$ and the space of certain Maa{\ss} forms of weight $k$ for $\Gamma$ to an isomorphism between the space of Siegel cusp forms of weight $k$ for a subgroup $\Gamma\subset\mathrm{Sp}_{n}(\mathbb{R})$, which is commensurable with the Siegel modular group $\mathrm{Sp}_{n}(\mathbb{Z})$, and a suitable space of Siegel-Maa{\ss} forms of weight $k$ for $\Gamma$.

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Jürg Kramer, Antareep Mandal. 2022-03-18. Relating Siegel cusp forms to Siegel-Maa{\ss} forms. https://doi.org/10.1007/s40993-022-00351-8

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