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arXiv · 1310.1361

Mean of the $L^\infty$-norm for $L^2$-normalized random waves on compact aperiodic Riemannian manifolds

Yaiza Canzani·Boris Hanin
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Abstract

This article concerns upper bounds for $L^\infty$-norms of random approximate eigenfunctions of the Laplace operator on a compact aperiodic Riemannian manifold $(M,g).$ We study $f_λ$ chosen uniformly at random from the space of $L^2$-normalized linear combinations of Laplace eigenfunctions with eigenvalues in the interval $(λ^2, \lr{λ+1}^2].$ Our main result is that the expected value of $\norm{f_λ}_\infty$ grows at most like $C \sqrt{\log λ}$ as $λ\to \infty$, where $C$ is an explicit constant depending only on the dimension and volume of $(M,g).$ In addition, we obtain concentration of the $L^\infty$-norm around its mean and median and study the analogous problems for Gaussian random waves on $(M,g).$

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BibTeXRIS

Yaiza Canzani, Boris Hanin. 2014-06-07. Mean of the $L^\infty$-norm for $L^2$-normalized random waves on compact aperiodic Riemannian manifolds. https://arxiv.org/abs/1310.1361

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