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Einstein four-manifolds of pinched sectional curvature

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 Added by Hung Tran
 Publication date 2016
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and research's language is English




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In this paper, we obtain classification of four-dimensional Einstein manifolds with positive Ricci curvature and pinched sectional curvature. In particular, the first result concerns with an upper bound of sectional curvature, improving a theorem of E. Costa. The second is a generalization of D. Yangs result assuming an upper bound on the difference between sectional curvatures.



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