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arXiv · 1612.06023

Einstein four-manifolds of pinched sectional curvature

Xiaodong Cao·Hung Tran
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Abstract

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. Yang's result assuming an upper bound on the difference between sectional curvatures.

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Xiaodong Cao, Hung Tran. 2016-12-19. Einstein four-manifolds of pinched sectional curvature. https://doi.org/10.1016/j.aim.2018.07.003

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