To date, I have been working on topics in twodimensional conformal field theories. These theories are covariant under local angle-preserving transformations. They play a role in statistical mechanics and in string theory. I have been interested in conformal field theories defined on a surface with a boundary; in string theory, this describes an excitation of a D-brane. There are situations in which the conformal symmetry is slightly broken, and the theory is subject to change under renormalization.

The renormalization process is presumably related to time-dependent processes in string theory, such as the decay of D-branes or a change in space-time itself. Here at IPMU, I intend to study topics in this direction.