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arXiv · 1502.02181

Chord-arc curves and the Beurling transform

K. Astala·M. J. González
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Abstract

We study the relation between the geometric properties of a quasicircle~$\Gamma$ and the complex dilatation~$\mu$ of a quasiconformal mapping that maps the real line onto~$\Gamma$. Denoting by~$S$ the Beurling transform, we characterize Bishop-Jones quasicircles in terms of the boundedness of the operator~$(I-\mu S)$ on a particular weighted $L^2$~space, and chord-arc curves in terms of its invertibility. As an application we recover the~$L^2$ boundedness of the Cauchy integral on chord-arc curves.

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K. Astala, M. J. González. 2015-02-07. Chord-arc curves and the Beurling transform. https://doi.org/10.1007/s00222-015-0630-8

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