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arXiv · 1609.02415

A family of compact strictly pseudoconvex hypersurfaces in $\mathbb C^2$ without umbilical points

Peter Ebenfelt·Duong Ngoc Son·Dmitri Zaitsev
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Abstract

We prove the following: For $\epsilon>0$, let $D_\epsilon$ be the bounded strictly pseudoconvex domain in $\mathbb C^2$ given by \begin{equation*} (\log|z|)^2+(\log|w|)^2<\epsilon^2. \end{equation*} The boundary $M_\epsilon:=\partial D_\epsilon\subset \mathbb C^2$ is a compact strictly pseudoconvex CR manifold without umbilical points. This resolves a long-standing question in complex analysis that goes back to the work of S.-S. Chern and J. K. Moser in 1974.

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Peter Ebenfelt, Duong Ngoc Son, Dmitri Zaitsev. 2016-09-08. A family of compact strictly pseudoconvex hypersurfaces in $\mathbb C^2$ without umbilical points. https://doi.org/10.4310/mrl.2018.v25.n1.a4

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