Some examples of manifolds of nonnegative curvature
نویسندگان
چکیده
منابع مشابه
Complete Manifolds of Nonnegative Curvature
The purpose of this survey is to give an overview of the results which characterize Riemannian manifolds with nonnegative or positive sectional, Ricci and scalar curvature, putting an emphasis on the differences between these increasingly strong conditions on curvature. All manifolds considered here are assumed to be complete. First we consider how nonnegative curvature is different from positi...
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We prove that if (M, g) is a compact locally irreducible Riemannian manifold with nonnegative isotropic curvature, then one of the following possibilities hold: (i) M admits a metric with positive isotropic curvature (ii) (M, g) is isometric to a locally symmetric space (iii) (M, g) is Kähler and biholomorphic to CP n. This is implied by the following two results: (i) Let (M, g) be a compact, l...
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In this short note, as a simple application of the strong result proved recently by Böhm and Wilking, we give a classification on closed manifolds with 2-nonnegative curvature operator. Moreover, by the new invariant cone constructions of Böhm and Wilking, we show that any complete Riemannian manifold (with dimension ≥ 3) whose curvature operator is bounded and satisfies the pinching condition ...
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ژورنال
عنوان ژورنال: Journal of Differential Geometry
سال: 1973
ISSN: 0022-040X
DOI: 10.4310/jdg/1214431964