Umbilic points and Real hyperquadrics

Won K. Park

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arXiv · math/9902035

Umbilic points and Real hyperquadrics

Won K. Park

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Abstract

We show a refined version of the existence and uniqueness theorem to Chern-Moser normal form. The class of nondegenerate real hypersurfaces in normal form has a natural group action. Umbilic point is defined via normal form. Nondegenerate analytic real hypersurfaces are locally biholomorphic to a real hyperquadric whenever every point is umbilic in this sense.

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Won K. Park. 1999-02-04. Umbilic points and Real hyperquadrics. https://arxiv.org/abs/math/9902035

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