 Speaker:  Catherine Meusburger 
Title: 
Grafting and Poisson structure in (2+1)gravity with vanishing
cosmological constant 
Abstract: 
The subject of the talk is the relation between the geometrical
construction of (2+1)dimensional spacetimes via grafting and phase
space and Poisson structure in the ChernSimons formulation of
(2+1)dimensional gravity. It discusses how grafting is implemented in
the ChernSimons formalism and how it gives rise to a transformation on
the phase space. This transformation is generated via the Poisson
bracket by a gauge invariant observable associated to certain curves in
the spacetime. Furthermore, it can be shown that this grafting
transformation is closely related to the action of Dehn twists.

Talk: 
Transparencies, Recorded Talk

 