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arXiv · 2204.03461

The CR Almost Schur Lemma and the positivity conditions

Stefan Ivanov·Alexander Petkov
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Abstract

We establish a new version of the CR almost Schur Lemma which gives an estimation of the pseudohermitian scalar curvature on a compact strictly pseudoconvex pseudohermitian manifold to be a constant in terms of the norm of the traceless Webster Ricci tensor and the pseudohermitian torsion under a certain positivity condition. In the torsion-free case, i.e. for a compact Sasakian manifold, our positivity condition coincides with the known one and we obtain a better estimate

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Stefan Ivanov, Alexander Petkov. 2022-04-07. The CR Almost Schur Lemma and the positivity conditions. https://arxiv.org/abs/2204.03461

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