Oscillatory functions vanish on a large set
Classical Analysis and ODEs
2018-05-09 v2 Analysis of PDEs
Abstract
Let be a dimensional, compact Riemannian manifold. We define the frequency scale of a function as the largest number such that for all Laplacian eigenfunctions with eigenvalue . If is large, then the function has to vanish on a large set Trigonometric functions on the flat torus show that the result is sharp up to a logarithm if . We also obtain a stronger result conditioned on the geometric regularity of . This may be understood as a very general higher-dimensional extension of the Sturm oscillation theorem.
Cite
@article{arxiv.1708.05373,
title = {Oscillatory functions vanish on a large set},
author = {Stefan Steinerberger},
journal= {arXiv preprint arXiv:1708.05373},
year = {2018}
}
Comments
v2, slightly improved results