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arXiv · 2306.14286

$L^2$ to $L^p$ bounds for spectral projectors on the Euclidean two-dimensional torus

Ciprian Demeter·Pierre Germain
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Abstract

We consider spectral projectors associated to the Euclidean Laplacian on the two-dimensional torus, in the case where the spectral window is narrow. Bounds for their L2 to Lp operator norm are derived, extending the classical result of Sogge; a new question on the convolution kernel of the projector is introduced. The methods employed include l2 decoupling, small cap decoupling, and estimates of exponential sums.

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Ciprian Demeter, Pierre Germain. 2023-06-25. $L^2$ to $L^p$ bounds for spectral projectors on the Euclidean two-dimensional torus. https://arxiv.org/abs/2306.14286

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