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arXiv · 2510.20934

On a Sharp Fourier Extension Inequality on the Circle with Lacunary Spectrum

Felipe Gonçalves·João Paulo Ferreira
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Abstract

We prove a sharp Fourier extension inequality on the circle for the Tomas-Stein exponent for functions whose spectrum $\{\pm \lambda_n\}$ satisfies $\lambda_{n+1}>3 \lambda_{n}$.

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Felipe Gonçalves, João Paulo Ferreira. 2025-10-23. On a Sharp Fourier Extension Inequality on the Circle with Lacunary Spectrum. https://arxiv.org/abs/2510.20934

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