Quasi-positively curved Riemannian manifold: Difference between revisions

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==Definition==
==Definition==


A [[Riemannian manifold]] <math>M</math> is said to have '''quasi-positive sectional curvature''' if the following are true:
A [[Riemannian manifold]] <math>M</math> is said to have '''quasi-positive sectional curvature''' or to be '''quasi-positively curved''' if the following are true:


* The sectional curvature is everywhere nonnegative
* The sectional curvature is everywhere nonnegative
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* [[Nonnegatively curved Riemannian manifold]]
* [[Nonnegatively curved Riemannian manifold]]
* [[Riemannian manifold with quasi-positive Ricci curvature]]
* [[Quasi-positive Ricci-curved Riemannian manifold]]

Latest revision as of 19:51, 18 May 2008

This article defines a property that makes sense for a Riemannian metric over a differential manifold

This article defines a property of Riemannian metrics based on the behaviour of the following curvature: sectional curvature

Definition

A Riemannian manifold is said to have quasi-positive sectional curvature or to be quasi-positively curved if the following are true:

  • The sectional curvature is everywhere nonnegative
  • There is a point for which the sectional curvature is strictly positive for all tangent planes

Relation with other properties

Stronger properties

Weaker properties