Title: Conformal invariants and semiconformal mappings
Speaker: Mike Eastwood (University of Adelaide):
Abstract: A submersion between two Riemannian manifolds is said to be semiconformal if it is conformal orthogonal to the fibres. Joint work with Paul Baird produces many examples semiconformal mappings from Euclidean 3-space to Euclidean 2-space and, under mild non-degeneracy assumptions, gives necessary and sufficient conditions in order that a function on 3-space be one of the components of such a mapping. These conditions are in the form of non-linear partial differential equations. They may also be regarded as conformal invariants of a smooth function. As such, some of these invariants have interesting geometric significance. Nothing much will be assumed of the audience and all terminology will be explained from scratch.