MathGloss

Let GG be a Lie group with associated Lie algebra g\mathfrak g. Then the adjoint map Ad:GGL(g)\text{Ad}:G \to \text{GL}(\mathfrak g) is given by AdA(X)=AXA1.\text{Ad}_A(X) = AXA^{-1}. Because the adjoint map is a Lie algebra homomorphism, it is a representation of g\mathfrak g, and therefore we may refer to ad\text{ad} as the adjoint representation of GG acting on g\mathfrak g when considered as a vector space.

Wikidata ID: Q1017106