Flat manifold — In mathematics, a Riemannian manifold is said to be flat if its curvature is everywhere zero. Intuitively, a flat manifold is one that locally looks like Euclidean space in terms of distances and angles, e.g. the interior angles of a triangle add … Wikipedia
Ricci curvature — In differential geometry, the Ricci curvature tensor, named after Gregorio Ricci Curbastro, provides one way of measuring the degree to which the geometry determined by a given Riemannian metric might differ from that of ordinary Euclidean n… … Wikipedia
Ricci flow — In differential geometry, the Ricci flow is an intrinsic geometric flow a process which deforms the metric of a Riemannian manifold in this case in a manner formally analogous to the diffusion of heat, thereby smoothing out irregularities in the… … Wikipedia
Ricci decomposition — In semi Riemannian geometry, the Ricci decomposition is a way of breaking up the Riemann curvature tensor of a pseudo Riemannian manifold into pieces with useful individual algebraic properties. This decomposition is of fundamental importance in… … Wikipedia
Einstein manifold — In differential geometry and mathematical physics, an Einstein manifold is a Riemannian or pseudo Riemannian manifold whose Ricci tensor is proportional to the metric. They are named after Albert Einstein because this condition is equivalent to… … Wikipedia
Calabi–Yau manifold — In mathematics, Calabi ndash;Yau manifolds are compact Kähler manifolds whose canonical bundle is trivial. They were named Calabi ndash;Yau spaces by physicists in 1985, [cite journal | author = Candelas, Horowitz, Strominger and Witten | year =… … Wikipedia
Complex manifold — In differential geometry, a complex manifold is a manifold with an atlas of charts to the open unit disk[1] in Cn, such that the transition maps are holomorphic. The term complex manifold is variously used to mean a complex manifold in the sense… … Wikipedia
Hyperkähler manifold — In differential geometry, a hyperkähler manifold is a Riemannian manifold of dimension 4 k and holonomy group contained in Sp( k ) (here Sp( k ) denotes a compact form of a symplectic group, identifiedwith the group of quaternionic linear unitary … Wikipedia
Sasakian manifold — In differential geometry, a Sasakian manifold is a contact manifold (M, heta) equipped with a special kind of Riemannian metric g, called a Sasakian metric.DefinitionA Sasakian metric is defined using the construction of the Riemannian cone .… … Wikipedia
G2 manifold — A G 2 manifold is a seven dimensional Riemannian manifold with holonomy group G 2. The group G 2 is one of the five exceptional simple Lie groups. It can be described as the automorphism group of the octonions, or equivalently, as a proper… … Wikipedia
