Langlands decomposition

In mathematics, the Langlands decomposition writes a parabolic subgroup P of a semisimple Lie group as a product P=MAN of a reductive subgroup M, an abelian subgroup A, and a nilpotent subgroup N.

Applications

A key application is in parabolic induction, which leads to the Langlands program: if G is a reductive algebraic group and P=MAN is the Langlands decomposition of a parabolic subgroup P, then parabolic induction consists of taking a representation of MA, extending it to P by letting N act trivially, and inducing the result from P to G.

See also

References