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arXiv · 1402.4635

The sup-norm problem for the Siegel modular space of rank two

Valentin Blomer·Anke Pohl
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Abstract

Let F be a square integrable Maass form on the Siegel upper half space of rank 2 for the Siegel modular group Sp(4, Z) with Laplace eigenvalue lambda. If, in addition, F is a joint eigenfunction of the Hecke algebra, we show a power-saving sup-norm bound in terms of lambda (relative to the generic bound) for F restricted to a compact set. As an auxiliary result of independent interest we prove new uniform bounds for spherical functions on semisimple Lie groups.

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Valentin Blomer, Anke Pohl. 2014-02-19. The sup-norm problem for the Siegel modular space of rank two. https://arxiv.org/abs/1402.4635

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