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arXiv · 1811.00397

A note on cusp forms and representations of $\mathrm{SL}_2(\mathbb{F}_p)$

Zhe Chen
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Abstract

Cusp forms are certain holomorphic functions defined on the upper half-plane, and the space of cusp forms for the principal congruence subgroup $Γ(p)$, $p$ a prime, is acted by $\mathrm{SL}_2(\mathbb{F}_p)$. Meanwhile, there is a finite field incarnation of the upper half-plane, the Deligne--Lusztig (or Drinfeld) curve, whose cohomology space is also acted by $\mathrm{SL}_2(\mathbb{F}_p)$. In this note we compute the relation between these two spaces in the weight $2$ case.

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BibTeXRIS

Zhe Chen. 2020-07-19. A note on cusp forms and representations of $\mathrm{SL}_2(\mathbb{F}_p)$. https://arxiv.org/abs/1811.00397

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