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arXiv · 1709.09795

Sharp $L^p$-$L^q$ estimates for the spherical harmonic projection

Yehyun Kwon·Sanghyuk Lee
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Abstract

We consider $L^p$-$L^q$ estimates for the spherical harmonic projection operators and obtain sharp bounds on a certain range of $p$, $q$. As an application, we provide a proof of off-diagonal Carleman estimates for the Laplacian, which extends the earlier results due to Jerison and Kenig \cite{JK}, and Stein \cite{St-append}.

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Yehyun Kwon, Sanghyuk Lee. 2017-09-28. Sharp $L^p$-$L^q$ estimates for the spherical harmonic projection. https://arxiv.org/abs/1709.09795

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