Analysis seminar
Speaker: Eyal Subag (Technion)
Title: A New Perspective on the Inonu-Wigner Contractions
Date: Thursday June 7 at 2:30 p.m.
Place: Amado 919.
Cookies: 10 minutes before the talk
Abstract: Many physical theories approximate other theories under certain limits.
Segal, Inonu and Wigner were the first to consider what are the implications
of these limits on the corresponding symmetry groups.
Contraction is a formal way of applying these limits to Lie groups, Lie
algebras and their representations.  In recent work we have shown that any
contraction of Lie algebra representations is intrinsically a direct limit
construction. Moreover, for any Inonu-Wigner contraction of a real three
dimensional Lie algebra, we obtained the corresponding contractions of the
irreducible representations in a canonical way by pointwise convergence of
differential operators. In this talk I'll review contraction of Lie algebras
and their representations focusing on the methods of Inonu and Wigner. I
will present several examples, some of which are new and show how the direct
limit construction arises naturally. This work was done in collaboration
with E. M. Baruch, J. L. Birman and A. Mann.

Seminar webpage:   <>
Technion Math. Net (TECHMATH)
Editor: Michael Cwikel   <> 
Announcement from: Tamar Ziegler   <>