SU(1,1), SU(2), and SU(3) coherence-preserving Hamiltonians and time-ordering techniques

Abstract
The Wei-Norman ordering technique is utilized to present a unified approach to the time ordering for SU(2), SU(1,1), and SU(3) coherence-preserving Hamiltonians. It is shown that the characteristic equations of the ordering method can be cast in the form of a generalized Bloch equation in an SU(2), SU(1,1), and SU(3) space. The laws of conservation, linked to the Casimir invariants of the algebra, are also directly derived from the Wei-Norman characteristic equations.