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arXiv · 1611.00264

Uniform rectifiability from Carleson measure estimates and $\varepsilon$-approximability of bounded harmonic functions

Abstract

Let $\Omega\subset\mathbb R^{n+1}$, $n\geq1$, be a corkscrew domain with Ahlfors-David regular boundary. In this paper we prove that $\partial\Omega$ is uniformly $n$-rectifiable if every bounded harmonic function on $\Omega$ is $\varepsilon$-approximable or if every bounded harmonic function on $\Omega$ satisfies a suitable square-function Carleson measure estimate. In particular, this applies to the case when $\Omega=\mathbb R^{n+1}\setminus E$ and $E$ is Ahlfors-David regular. Our results solve a conjecture posed by Hofmann, Martell, and Mayboroda in a recent work where they proved the converse statements. Here we also obtain two additional criteria for uniform rectifiability. One is given in terms of the so-called "$S<N$" estimates, and another in terms of a suitable corona decomposition involving harmonic measure.

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BibTeXRIS

John Garnett, Mihalis Mourgoglou, Xavier Tolsa. 2016-11-01. Uniform rectifiability from Carleson measure estimates and $\varepsilon$-approximability of bounded harmonic functions. https://doi.org/10.1215/00127094-2017-0057

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