Riemannian Manifold
In differential geometry, a (smooth) Riemannian manifold or (smooth) Riemannian space (M,g) is a real smooth manifold M equipped with an inner product on each tangent space that varies smoothly from point to point in the sense that if X and Y are vector fields on M, then is a smooth function. The family of inner products is called a Riemannian metric (tensor). These terms are named after the German mathematician Bernhard Riemann. The study of Riemannian manifolds comprises the subject called Riemannian geometry.
A Riemannian metric (tensor) makes it possible to define various geometric notions on a Riemannian manifold, such as angles, lengths of curves, areas (or volumes), curvature, gradients of functions and divergence of vector fields.
Read more about Riemannian Manifold: Introduction, Overview, Riemannian Metrics, Riemannian Manifolds As Metric Spaces
Famous quotes containing the word manifold:
“She ran down the stair
A twelve-year-old darling
And laughing and calling
She tossed her bright hair;”
—John Streeter Manifold (b. 1915)