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arXiv · 1706.02771

On the global sup-norm of GL(3) cusp forms

Abstract

Let $ϕ$ be a spherical Hecke-Maass cusp form on the non-compact space $\mathrm{PGL}_3(\mathbb{Z})\backslash\mathrm{PGL}_3(\mathbb{R})$. We establish various pointwise upper bounds for $ϕ$ in terms of its Laplace eigenvalue $λ_ϕ$. These imply, for $ϕ$ arithmetically normalized and tempered at the archimedean place, the bound $\|ϕ\|_\infty\ll_ελ_ϕ^{39/40+ε}$ for the global sup-norm (without restriction to a compact subset). On the way, we derive a new uniform upper bound for the $\mathrm{GL}_3$ Jacquet-Whittaker function.

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BibTeXRIS

Valentin Blomer, Gergely Harcos, Péter Maga. 2018-03-29. On the global sup-norm of GL(3) cusp forms. https://doi.org/10.1007/s11856-018-1805-y

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