Functional Calculus and Coadjoint Orbits

ISBN-13: 9783639155785 / Angielski / Miękka / 2009 / 96 str.

Raed Raffoul

Opis

The Kirillov character formula gives a striking correspondence between the unitary irreducible representations of a compact semisimple Lie group and its set of integral orbits on the dual of its Lie algebra. In this thesis, the same correspondence is derived without the use of character theory. It is shown to be related to the convexity properties of the support of the Weyl functional calculus of the infinitesimal generators of the representation. This result uses Edward Nelson's theory of "operants" in a fundamental way. This had been developed to put Feynman's operator calculus on a rigorous basis. In particular, a beautiful explicit formula of Nelson for the Weyl calculus facilitates the extension of the Kirillov formula to the matrix coefficients of the representation, thus giving a "non-commutative" Kirillov-type formula for compact Lie groups.

O autorze

Raed Raffoul completed a B.Sc.(Hons) at the University of Sydney
and a Ph.D. in harmonic analysis on Lie groups at the University
of New South Wales.