Hadamard manifold
In mathematics, a Hadamard manifold, named after Jacques Hadamard — more often called a Cartan–Hadamard manifold, after Élie Cartan — is a Riemannian manifold (M, g) that is complete and simply connected and has everywhere non-positive sectional curvature.[1][2] By Cartan–Hadamard theorem all Cartan–Hadamard manifold are diffeomorphic to the Euclidean space . Furthermore it follows from the Hopf–Rinow theorem that every pairs of points in a Cartan–Hadamard manifold may be connected by a unique geodesic segment. Thus Cartan–Hadamard manifolds are some of the closest relatives of .
Examples
- The Euclidean space Rn with its usual metric is a Cartan-Hadamard manifold with constant sectional curvature equal to 0.
- Standard n-dimensional hyperbolic space Hn is a Cartan-Hadamard manifold with constant sectional curvature equal to −1.
Properties
- In Cartan-Hadamard Manifolds, the map expp mapping TMp to M is a covering map for all p in M.
gollark: Yep!
gollark: But in any case don't do that. If you are doing that, please reevaluate your life choices.
gollark: Probably just not add new ones.
gollark: I don't think so.
gollark: How about "read file, parse/compile Lua source code and execute resulting function"? That seems clear.
References
- Li, Peter (2012). Geometric Analysis. Cambridge University Press. p. 381. ISBN 9781107020641.
- Lang, Serge (1989). Fundamentals of Differential Geometry, Volume 160. Springer. pp. 252–253. ISBN 9780387985930.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.