Schur 's lemma admits generalisations to Lie groups and Lie algebras , the most common of which is due to Jacques Dixmier .
The lemma is named after Issai Schur who used it to prove Schur orthogonality relations and develop the basics of the representation theory of finite groups .
Schur 's lemma admits generalisations to Lie groups and Lie algebras , the most common of which is due to Jacques Dixmier .
The lemma is named after Issai Schur who used it to prove Schur orthogonality relations and develop the basics of the representation theory of finite groups .