Cartan–Karlhede algorithm

The Cartan–Karlhede algorithm is a procedure for completely classifying and comparing Riemannian manifolds. Given two Riemannian manifolds of the same dimension, it is not always obvious whether they are locally isometric. Élie Cartan, using his exterior calculus with his method of moving frames, showed that it is always possible to compare the manifolds. Carl Brans developed the method further, and the first practical implementation was presented by in 1980.

Comment
enThe Cartan–Karlhede algorithm is a procedure for completely classifying and comparing Riemannian manifolds. Given two Riemannian manifolds of the same dimension, it is not always obvious whether they are locally isometric. Élie Cartan, using his exterior calculus with his method of moving frames, showed that it is always possible to compare the manifolds. Carl Brans developed the method further, and the first practical implementation was presented by in 1980.
Has abstract
enThe Cartan–Karlhede algorithm is a procedure for completely classifying and comparing Riemannian manifolds. Given two Riemannian manifolds of the same dimension, it is not always obvious whether they are locally isometric. Élie Cartan, using his exterior calculus with his method of moving frames, showed that it is always possible to compare the manifolds. Carl Brans developed the method further, and the first practical implementation was presented by in 1980. The main strategy of the algorithm is to take covariant derivatives of the Riemann tensor. Cartan showed that in n dimensions at most n(n+1)/2 differentiations suffice. If the Riemann tensor and its derivatives of the one manifold are algebraically compatible with the other, then the two manifolds are isometric. The Cartan–Karlhede algorithm therefore acts as a kind of generalization of the Petrov classification. The potentially large number of derivatives can be computationally prohibitive. The algorithm was implemented in an early symbolic computation engine, SHEEP, but the size of the computations proved too challenging for early computer systems to handle. For most problems considered, far fewer derivatives than the maximum are actually required, and the algorithm is more manageable on modern computers. On the other hand, no publicly available version exists in more modern software.
Hypernym
Procedure
Is primary topic of
Cartan–Karlhede algorithm
Label
enCartan–Karlhede algorithm
Link from a Wikipage to an external page
web.archive.org/web/20051023160408/http:/130.15.26.66/servlet/GRDB2.GRDBServlet
Link from a Wikipage to another Wikipage
Carl Brans
Category:Mathematical methods in general relativity
Category:Riemannian geometry
Compact group
Computer algebra system
Covariant derivative
Curvature invariant
Definite bilinear form
Élie Cartan
Exterior derivative
Fluid solution
Frame fields in general relativity
General relativity
Lie group
Local isometry
Lorentz group
Metric tensor
Moving frames
Null dust solution
Petrov classification
Riemannian manifold
Riemann tensor
SHEEP (symbolic computation system)
Vacuum solution (general relativity)
Vanishing scalar invariant spacetime
SameAs
4ftwj
Algoritmo de Cartan-Karlhede
m.07xjmq
Q5047049
Subject
Category:Mathematical methods in general relativity
Category:Riemannian geometry
WasDerivedFrom
Cartan–Karlhede algorithm?oldid=1061337626&ns=0
WikiPageLength
5826
Wikipage page ID
2680495
Wikipage revision ID
1061337626
WikiPageUsesTemplate
Template:Ill