Planar algebras and subfactors

Paramita Das
Abstract
In the classification program of `subfactors' (i.e., inclusions of certain types of von Neumann algebras), the most important invariant is the `standard invariant' which had been reformulated by Vaughan Jones in terms of pictures on a plane, which he named `Planar Algebras'. Since its inception, planar algebras turned out to be a very useful tool in the theory of subfactors, namely in constructing new subfactors, detecting the existence of subfactors associated with certain graphs, etc. In this talk I will first describe these objects and the connection between them as given by Jones' theorem. I will then discuss a few recent results obtained in this area.