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Pointwise convergence of lacunary spherical means

Andreas Seeger·Terence Tao·James Wright
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Abstract

We show that if $f$ is locally in $L\log\log L$ then the lacunary spherical means converge almost everywhere. The argument given here is a model case for more general results on singular maximal functions and Radon transforms (see ref. 6).

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Andreas Seeger, Terence Tao, James Wright. 2002-05-14. Pointwise convergence of lacunary spherical means. https://arxiv.org/abs/math/0205154

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