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arXiv · 1710.04959

The Loewner energy of loops and regularity of driving functions

Steffen Rohde·Yilin Wang
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Abstract

Loewner driving functions encode simple curves in 2-dimensional simply connected domains by real-valued functions. We prove that the Loewner driving function of a $C^{1,β}$ curve (differentiable parametrization with $β$-Hölder continuous derivative) is in the class $C^{1,β-1/2}$ if $1/2<β\leq 1$, and in the class $C^{0,β+ 1/2}$ if $0 \leq β\leq 1/2$. This is the converse of a result of Carto Wong and is optimal. We also introduce the Loewner energy of a rooted planar loop and use our regularity result to show the independence of this energy from the basepoint.

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Steffen Rohde, Yilin Wang. 2019-03-13. The Loewner energy of loops and regularity of driving functions. https://doi.org/10.1093/imrn%2Frnz071

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