• In mathematics, spaces of non-positive curvature occur in many contexts and form a generalization of hyperbolic geometry. In the category of Riemannian...
    5 KB (660 words) - 17:40, 29 January 2024
  • curved space is hyperbolic geometry (see also: non-positive curvature). A space or space-time with zero curvature is called flat. For example, Euclidean space...
    44 KB (6,461 words) - 21:09, 16 September 2024
  • {CAT} (k)} neighbourhood. A space with curvature ≤ 0 {\displaystyle \leq 0} may be said to have non-positive curvature. Any CAT ⁡ ( k ) {\displaystyle \operatorname...
    13 KB (1,995 words) - 01:22, 31 January 2024
  • geometry, the sectional curvature is one of the ways to describe the curvature of Riemannian manifolds. The sectional curvature K(σp) depends on a two-dimensional...
    20 KB (3,103 words) - 21:48, 5 January 2024
  • X {\displaystyle X} be a simply-connected manifold of non-positive bounded sectional curvature. There exist constants C , ε > 0 {\displaystyle C,\varepsilon...
    8 KB (1,185 words) - 18:50, 26 January 2024
  • concerning the structure of complete Riemannian manifolds of non-positive sectional curvature. The theorem states that the universal cover of such a manifold...
    8 KB (968 words) - 01:48, 3 March 2023
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    Gaussian curvature or Gauss curvature Κ of a smooth surface in three-dimensional space at a point is the product of the principal curvatures, κ1 and κ2...
    19 KB (2,612 words) - 22:21, 7 August 2024
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    there is positive curvature. If Ω < 1, there is negative curvature. Scientists could experimentally calculate Ω to determine the curvature two ways....
    30 KB (3,840 words) - 21:17, 12 September 2024
  • In differential geometry, the Ricci curvature tensor, named after Gregorio Ricci-Curbastro, is a geometric object which is determined by a choice of Riemannian...
    34 KB (5,859 words) - 04:51, 6 July 2024
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    Bridson, Martin R.; Haefliger, André (1999). Metric spaces of non-positive curvature. Grundlehren der mathematischen Wissenschaften. Vol. 319. Berlin:...
    116 KB (10,419 words) - 07:02, 13 September 2024