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arXiv · 1410.7260

Berger curvature decomposition, Weitzenb\"ock formula, and canonical metrics on four-manifolds

Peng Wu
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Abstract

We first provide an alternative proof of the classical Weitzneb\"ock formula for Einstein four-manifolds using Berger curvature decomposition, motivated by which we establish a unified framework for a Weitzenb\"ock formula for a large class of canonical metrics on four-manifolds (or a Weitzenb\"ock formula for "Einstein metrics" on four-dimensional smooth metric measure spaces). As applications, we classify Einstein four-manifolds of half two-nonnegative curvature operator, which in some sense provides a characterization of K\"ahler-Einstein metrics with positive scalar curvature on four-manifolds, we also discuss four-manifolds of half two-nonnegative curvature operator and half harmonic Weyl curvature.

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Peng Wu. 2014-10-27. Berger curvature decomposition, Weitzenb\"ock formula, and canonical metrics on four-manifolds. https://arxiv.org/abs/1410.7260

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