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arXiv · 2504.02621

Chern's Conjecture in the Dupin case

Reiko Miyaoka
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Abstract

Chern's conjecture states that a closed minimal hypersurface in the euclidean sphere is isoparametric if it has constant scalar curvature. When the number $g$ of distinct principal curvatures is greater than three, few satisfactory results have been known. We attack the conjecture in the Dupin hypersurface case. Our results are: A closed proper Dupin hypersurface with constant mean curvature is isoparametric (i) if $g=3$, (ii) if $g=4$ and has constant scalar curvature, or (iii) if $g=4$ and has constant Lie curvature, and (iv) if $g=6$ and has constant Lie curvatures. These cover all the non-trivial cases for a closed proper Dupin to be isoparametric since $g$ can take only values $1,2,3,4,6$. The originality of the proof is a use of topology and geometry, which reduces assumptions needed in the algebraic argument.

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Reiko Miyaoka. 2025-04-03. Chern's Conjecture in the Dupin case. https://arxiv.org/abs/2504.02621

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