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arXiv · 1804.10463

A comparison principle for convolution measures with applications

Diogo Oliveira e Silva·René Quilodrán
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Abstract

We establish the general form of a geometric comparison principle for $n$-fold convolutions of certain singular measures in $\mathbb{R}^d$ which holds for arbitrary $n$ and $d$. This translates into a pointwise inequality between the convolutions of projection measure on the paraboloid and a perturbation thereof, and we use it to establish a new sharp Fourier extension inequality on a general convex perturbation of a parabola. Further applications of the comparison principle to sharp Fourier restriction theory are discussed in a companion paper.

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Diogo Oliveira e Silva, René Quilodrán. 2018-05-02. A comparison principle for convolution measures with applications. https://doi.org/10.1017/s0305004119000197

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