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arXiv · 1712.05549

Finite field restriction estimates for the paraboloid in high even dimensions

Alex Iosevich·Doowon Koh·Mark Lewko
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Abstract

We prove that the finite field Fourier extension operator for the paraboloid is bounded from $L^2\to L^r$ for $r\geq \frac{2d+4}{d}$ in even dimensions $d\ge 8$, which is the optimal $L^2$ estimate. For $d=6$ we obtain the optimal range $r> \frac{2d+4}{d}=8/3$, apart from the endpoint. For $d=4$ we improve the prior range of $r>16/5=3.2$ to $r\geq 28/9=3.111\ldots$, compared to the conjectured range of $r\geq3$. The key new ingredient is improved additive energy estimates for subsets of the paraboloid.

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Alex Iosevich, Doowon Koh, Mark Lewko. 2017-12-15. Finite field restriction estimates for the paraboloid in high even dimensions. https://arxiv.org/abs/1712.05549

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