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arXiv · 1604.01699

The $L^2$ Behavior of Eigenfunctions Near the Glancing Set

Jeffrey Galkowski
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Abstract

Let $M$ be a compact manifold with or without boundary and $H\subset M$ be a smooth, interior hypersurface. We study the restriction of Laplace eigenfunctions solving $(-h^2Δ_g-1)u=0$ to $H$. In particular, we study the degeneration of $u|_H$ as one microlocally approaches the glancing set by finding the optimal power $s_0$ so that $(1+h^2Δ_H)_+^{s_0}u|_H$ remains uniformly bounded in $L^2(H)$ as $h\to 0$. Moreover, we show that this bound is saturated at every $h$-dependent scale near glancing using examples on the disk and sphere. We give an application of our estimates to quantum ergodic restriction theorems.

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Jeffrey Galkowski. 2016-04-06. The $L^2$ Behavior of Eigenfunctions Near the Glancing Set. https://doi.org/10.1080/03605302.2016.1227339

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