Cartan–Killing form
E542117
Lie algebra invariant
bilinear form
invariant bilinear form
mathematical object
symmetric bilinear form
The Cartan–Killing form is a canonical symmetric bilinear form on a Lie algebra that plays a central role in classifying and studying the structure of Lie algebras and Lie groups.
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
Lie algebra invariant
ⓘ
bilinear form ⓘ invariant bilinear form ⓘ mathematical object ⓘ symmetric bilinear form ⓘ |
| alsoKnownAs | Killing form NERFINISHED ⓘ |
| appliesTo | finite-dimensional Lie algebras over fields of characteristic zero ⓘ |
| belongsToField |
Lie theory
ⓘ
differential geometry ⓘ representation theory ⓘ |
| characterizes | semisimple Lie algebras via nondegeneracy ⓘ |
| definedOn | Lie algebra ⓘ |
| hasProperty |
ad-invariant
ⓘ
bilinear ⓘ degenerate on solvable Lie algebras ⓘ invariant under adjoint representation ⓘ negative definite on compact semisimple Lie algebras ⓘ nondegenerate on semisimple Lie algebras ⓘ symmetric ⓘ trace form ⓘ |
| isCanonicalOn | semisimple Lie algebra ⓘ |
| isDefinedBy | K(x,y) = Trace(ad(x) ∘ ad(y)) ⓘ |
| isGivenBy | trace of composition of adjoint endomorphisms ⓘ |
| isInvariantUnder |
adjoint action of Lie group
ⓘ
inner automorphisms of Lie algebra ⓘ |
| isProportionalTo | any other invariant symmetric bilinear form on a simple Lie algebra ⓘ |
| isUsedFor |
classification of complex semisimple Lie algebras
ⓘ
classification of real semisimple Lie algebras ⓘ classification of semisimple Lie algebras ⓘ classification of simple Lie algebras ⓘ construction of Dynkin diagrams ⓘ decomposition of Lie algebras ⓘ definition of Cartan subalgebras ⓘ definition of Casimir operator ⓘ definition of dual Coxeter number ⓘ definition of invariant Riemannian metric on Lie group ⓘ definition of metric on Lie algebra ⓘ definition of root systems ⓘ detection of semisimplicity ⓘ study of Lie algebra structure ⓘ study of Lie group structure ⓘ |
| isUsedToDefine |
Cartan matrix
NERFINISHED
ⓘ
Weyl group reflections NERFINISHED ⓘ angles between roots ⓘ lengths of roots ⓘ orthogonality of roots ⓘ |
| namedAfter |
Wilhelm Killing
NERFINISHED
ⓘ
Élie Cartan NERFINISHED ⓘ |
| restrictsTo | nondegenerate form on derived algebra of semisimple Lie algebra ⓘ |
| vanishesOn | center of a Lie algebra ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
Élie Cartan