A conformally invariant sphere theorem in four dimensions

S. Y. A Chang; Matthew J. Gursky; Paul Yang

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A conformally invariant sphere theorem in four dimensions

S. Y. A Chang·Matthew J. Gursky·Paul Yang

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Abstract

In this paper we provide a sharp characterization of the smooth four-dimensional sphere. The assumptions of the theorem are conformally invariant, and can be reduced to an L^2 inequality of the Weyl tensor and positivity of the Yamabe invariant.

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S. Y. A Chang, Matthew J. Gursky, Paul Yang. 2003-09-17. A conformally invariant sphere theorem in four dimensions. https://arxiv.org/abs/math/0309287

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