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An equation of Monge-Ampere type in conformal geometry, and four-manifolds of positive Ricci curvature

Sun-Yung A. Chang·Matthew J. Gursky·Paul C. Yang
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Abstract

We formulate natural conformally invariant conditions on a 4-manifold for the existence of a metric whose Schouten tensor satisfies a quadratic inequality. This inequality implies that the eigenvalues of the Ricci tensor are positively pinched.

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Sun-Yung A. Chang, Matthew J. Gursky, Paul C. Yang. 2004-09-29. An equation of Monge-Ampere type in conformal geometry, and four-manifolds of positive Ricci curvature. https://arxiv.org/abs/math/0409583

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