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arXiv · 1303.2325

Bilipschitz and quasiconformal rotation, stretching and multifractal spectra

Kari Astala·Tadeusz Iwaniec·István Prause·Eero Saksman
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Abstract

We establish sharp bounds for simultaneous local rotation and H\"older-distortion of planar quasiconformal maps. In addition, we give sharp estimates for the corresponding joint quasiconformal multifractal spectrum, based on new estimates for Burkholder functionals with complex parameters. As a consequence, we obtain optimal rotation estimates also for bi-Lipschitz maps.

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Kari Astala, Tadeusz Iwaniec, István Prause, Eero Saksman. 2013-03-10. Bilipschitz and quasiconformal rotation, stretching and multifractal spectra. https://doi.org/10.1007/s10240-014-0065-6

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