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arXiv · 1705.04572

Computing Invariants of the Weil representation

Stephan Ehlen·Nils-Peter Skoruppa
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Abstract

We propose an algorithm for computing bases and dimensions of spaces of invariants of Weil representations of $\mathrm{SL}_2(\mathbb{Z})$ associated to finite quadratic modules. We prove that these spaces are defined over $\mathbb{Z}$, and that their dimension remains stable if we replace the base field by suitable finite prime fields.

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Stephan Ehlen, Nils-Peter Skoruppa. 2017-05-12. Computing Invariants of the Weil representation. https://arxiv.org/abs/1705.04572

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