Einstein Four-manifolds of Three-nonnegative Curvature Operator
نویسندگان
چکیده
We prove that Einstein four-manifolds with three-nonnegative curvature operator are either flat, isometric to (S, g0), (CP , gFS), (S × S, g0 ⊕ g0), or their quotients by finite groups of fixed point free isometries, up to rescaling. We also prove that Einstein four-manifolds with four-nonnegative curvature operator and positive intersection form are isometric to (CP , gFS) up to rescaling.
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تاریخ انتشار 2014