Hyperbolic Point
A point p on a regular surface M in R^3 is said to be hyperbolic if the Gaussian curvature K(p)<0 or equivalently, the principal curvatures kappa_1 and kappa_2, have opposite signs.
See also
Anticlastic, Elliptic Point, Gaussian Curvature, Hyperbolic Fixed Point, Parabolic Point, Planar Point, SynclasticExplore with Wolfram|Alpha
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References
Gray, A. Modern Differential Geometry of Curves and Surfaces with Mathematica, 2nd ed. Boca Raton, FL: CRC Press, p. 375, 1997.Referenced on Wolfram|Alpha
Hyperbolic PointCite this as:
Weisstein, Eric W. "Hyperbolic Point." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/HyperbolicPoint.html