منابع مشابه
Cohomogeneity One Actions on Noncompact Symmetric Spaces of Rank One
We classify, up to orbit equivalence, all cohomogeneity one actions on the hyperbolic planes over the complex, quaternionic and Cayley numbers, and on the complex hyperbolic spaces CHn, n ≥ 3. For the quaternionic hyperbolic spaces HHn, n ≥ 3, we reduce the classification problem to a problem in quaternionic linear algebra and obtain partial results. For real hyperbolic spaces, this classificat...
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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 ...
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ژورنال
عنوان ژورنال: Transformation Groups
سال: 2011
ISSN: 1083-4362,1531-586X
DOI: 10.1007/s00031-011-9122-0