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arXiv · 1506.00157

Near equality in the Riesz-Sobolev inequality in higher dimensions

Michael Christ
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Abstract

The Riesz-Sobolev inequality provides an upper bound for a trilinear expression involving convolution of indicator functions of sets. It is known that equality holds only for homothetic ordered triples of appropriately situated ellipsoids. We characterize ordered triples of subsets of Euclidean space $R^d$ that nearly realize equality, for arbitrary dimensions $d$, extending a result already known for $d=1$.

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Michael Christ. 2015-05-30. Near equality in the Riesz-Sobolev inequality in higher dimensions. https://arxiv.org/abs/1506.00157

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