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Einstein four-manifolds of pinched sectional curvature

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 نشر من قبل Hung Tran
 تاريخ النشر 2016
  مجال البحث
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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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