Quasigeodesics and Gradient Curves in Alexandrov Spaces
نویسندگان
چکیده
1. A comparison theorem for complete Riemannian manifolds with sectional curvatures ≥ k says that distance functions in such manifolds are more concave than in the model space Sk of constant curvature k. In other words, the restriction of any distance function distp to any geodesic γ (always parametrised by the arclength) satisfies a certain concavity condition (∗)k. For example, the condition (∗)o reads
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تاریخ انتشار 2003