Angular Momentum and Lie Algebras

Alvin Meckler

D. Sourias, A. D. Jannussis, A. Streclas

In this paper we study the Wigner operators of angular momentum in the phase space, which are obtained from the well-known operators of angular momentum by virtue of Wigner representation. In the sequel we construct the Lie algebra of these operators, as well as the corresponding Lie group, and we examine two representations of this group. We find also the eigenfunction and the eigenvalues of these operators.

BAO JIAN-REN, Zhou Lu-wei, 复旦大学物理系

The association and difference between general angular momentum and orbital angular momentum are discussed. Their association lies in the identity of local property (Lie algebra) between group SU (2) and SO (3) (isomorphism), while their difference is their distinctive integral property. The minimal unit ?/2 of the general angular momentum is determined by the local properties of the groups, namely the commutation relation of Lie algebra (or commutor of angular momentum). However, the minimal unit ? of orbital angular momentum depends upon the integral property of group SO (3).

Stephen P. Martin