Adam Biggs (University of Manchester)
adam.biggs-2@postgrad.manchester.ac.uk
We shall discuss the concept of a pencil lifting for the algebra of densities. In particular we will classify the space of liftings that are equivariant with respect to some natural groups: the group of all diffeomorphisms, the group of diffeomorphisms that preserve a volume form, and the projective group. Using these constructions we can find cocycles of the group of diffeomorphisms and we shall go through these constructions.