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arXiv · 1706.06507

A sharp version of the H\"ormander multiplier theorem

Loukas Grafakos·Lenka Slavíková
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Abstract

We provide an improvement of the H\"ormander multiplier theorem in which the Sobolev space $L^r_s(\mathbb R^n)$ with integrability index $r$ and smoothness index $s>n/r$ is replaced by the Sobolev space with smoothness $s$ built upon the Lorentz space $L^{n/s,1}(\mathbb R^n)$.

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Loukas Grafakos, Lenka Slavíková. 2017-06-20. A sharp version of the H\"ormander multiplier theorem. https://arxiv.org/abs/1706.06507

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