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arXiv · 2508.09940

Sharp quantitative integral inequalities for harmonic extensions

Rupert L. Frank·Jonas W. Peteranderl·Larry Read
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Abstract

We prove a quantitative version of a sharp integral inequality by Hang, Wang, and Yan for both the Poisson operator and its adjoint. Our result has the strongest possible norm and the optimal stability exponent. This stability exponent is not necessarily equal to 2, displaying the same phenomenon that Figalli and Zhang observed for the $p$-Sobolev inequality.

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Rupert L. Frank, Jonas W. Peteranderl, Larry Read. 2025-08-13. Sharp quantitative integral inequalities for harmonic extensions. https://arxiv.org/abs/2508.09940

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