Manchester Geometry Seminar 2001/2002


14 February 2002. Room 9.05, Mathematics Building, University of Manchester. 3pm

Singular Dual Pairs and Optimal Momentum Maps

Juan-Pablo Ortega (Institut Non Linéaire de Nice)


Juan-Pablo.Ortega@inln.cnrs.fr

We generalize the notions of dual pair and polarity introduced by S. Lie and A. Weinstein in order to accommodate very relevant situations where the application of these ideas is desirable. The new notion of polarity is designed to deal with the loss of smoothness caused by the presence of singularities that are encountered in many problems in Poisson and symplectic geometry. We study in detail the relation between the newly introduced dual pairs, the quantum notion of Howe pair, and the symplectic leaf correspondence of Poisson manifolds in duality. The dual pairs arising in the context of symmetric Poisson manifolds are treated with special attention. We show that in this case and under very reasonable hypotheses we obtain a particularly well behaved kind of dual pairs that we call von Neumann pairs. Some of the ideas that we present in this talk shed some light on the so called optimal momentum maps that will be also discussed.

See
http://front.math.ucdavis.edu/math.SG/0201192


http://www.ma.umist.ac.uk/tv/seminar.html