Sj. Wang et al., CONTINUOUS-VARIABLE REPRESENTATION OF DYNAMIC GROUPS IN QUANTUM-SYSTEMS .2. THE EXTREME-EIGENSTATE APPROACH, Physical review. A, 47(6), 1993, pp. 4641-4648
The extreme-eigenstate approach to the solution of dynamic group repre
sentation is formulated systematically based on the continuous represe
ntation of the group generators and their intrinsic counterparts by vi
rtue of two complete sets of commuting operators of first and second k
inds (CSCO I and CSCO II). The high-order partial differential equatio
ns for the general representation eigenstates in the conventional appr
oach are replaced by a set of first-order partial differential equatio
ns for the extreme eigenstate in this approach. This set of first-orde
r partial differential equations is tractable for analytical solutions
. By applying the ladder operators, any representation eigenstates can
be obtained by standard differential operation. In application, the W
iper SU(2) D function and the Elliott SU(3) irreducible representation
basis are obtained by this approach as illustrations. The approach is
proved to be simple, useful, and efficient for physicists.