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arXiv · 1307.1825

On Wintgen ideal surfaces

Bang-Yen Chen
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Abstract

Wintgen proved in [P. Wintgen, Sur l'inégalité de Chen-Willmore, C. R. Acad. Sci. Paris, 288 (1979), 993--995] that the Gauss curvature $K$ and the normal curvature $K^D$ of a surface in the Euclidean 4-space $E^4$ satisfy $$K+|K^D|\leq H^2,$$ where $H^2$ is the squared mean curvature. A surface $M$ in $\E4$ is called a {Wintgen ideal} surface if it satisfies the equality case of the inequality identically. Wintgen ideal surfaces in $E^4$ form an important family of surfaces; namely, surfaces with circular ellipse of curvature. In this paper, we provide a brief survey on some old and recent results on Wintgen ideal surfaces and more generally Wintgen ideal submanifolds in definite and indefinite real space forms.

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Bang-Yen Chen. 2013-07-07. On Wintgen ideal surfaces. https://arxiv.org/abs/1307.1825

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