A decoupling proof of the Tomas restriction theorem

Griffin Pinney

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arXiv · 2112.04111

A decoupling proof of the Tomas restriction theorem

Griffin Pinney

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Abstract

We give a new proof of a classic Fourier restriction theorem for the truncated paraboloid in $\mathbb{R}^n$ based on the $l^2$ decoupling theorem of Bourgain-Demeter. Focusing on the extension formulation of the restriction problem (dual to the original restriction formulation), we find that the $l^2$ decoupling theorem directly implies a local variant of the desired extension estimate incurring an $\varepsilon$-loss. To upgrade this result to the desired global extension estimate, we employ some $\varepsilon$-removal techniques first introduced by Tao. By adhering to the extension formulation, we obtain a more natural proof of the required $\varepsilon$-removal result.

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BibTeX RIS

Griffin Pinney. 2021-12-08. A decoupling proof of the Tomas restriction theorem. https://arxiv.org/abs/2112.04111

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