Constrained systems: Dirac and post-Dirac quantisation
Seminar Room 1, Newton Institute
I will first review Dirac's procedure of quantising (first class) constrained systems, discussing the mathematical structure that a quantisation should provide. I will then specialise to systems whose gauge group is a Lie group and address group averaging as a method of implementing the quantisation. The case of a noncompact gauge group, and the open questions therein, will be emphasised in view of its relevance for quantum gravity.