Monodromy, Duality and Integrability of Two Dimensional String Effective Action

Abstract

In this talk, we show how the monodromy matrix, $\hat{\mathcal{M}}$, can be constructed for the two dimensional tree level string effective action. The pole structure of $\hat{\mathcal{M}}$ is derived using its factorizability property. It is shown that the monodromy matrix transforms non-trivially under the non-compact T-duality group, which leaves the effective action invariant and this can be used to construct the monodromy matrix for more complicated backgrounds starting from simpler ones. We construct, explicitly, $\hat{\mathcal{M}}$ for the exactly solvable Nappi-Witten model, both when B=0 and $B\ne 0$, where these ideas can be directly checked.

20 pages, to appear in the proceedings of the Workshop on Integrable Field Theories, Solitons and Duality, Sao Paulo, July 1-6, 2002