>VITAE:
Hubert de Guise obtained his Ph.D. in mathematical nuclear physics from the University of Toronto in 1996. National postdoctoral scholar and a provincial postdoctoral scholar for a total of four years in the Centre de Recherches Mathematiques at Universite de Montreal, heleft Montreal for a one-year appointment at Faculte St-Jean of the University of Alberta in Edmonton, and moved to Thunder Bay in summer 2001 with a position of Assistant Professor in the Department of Physics at Lakehead University.

Hubert de Guise research interests are in Lie algebraic methods in physics, with a current emphasis on su(n) algebras, their related groups and associated unitary representations. He has done work on contractions, deformations, and asymptotic limits associated with the representations of various algebras, particularly in connection with coherent state representations and asymptotic coupling coefficients. Early applications included nuclear collective motion but are now focused on problems related to finite subgroups of SU(n), complementarity in SU(n) and associated finite field methods.

This talk will focus on how a physicist can understand the various possible limits of SU(2) and SU(3) Wigner d-functions. It will be shown how various limits correspond to different realizations of the corresponding algebras, and how these different realizations are expected to occur in different physical regimes of a two-mode and a three-mode oscillator. Some unresolved issues will be discussed.