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Monodromy, Duality and Integrability of Two Dimensional String Effective Action

Ashok Das·J. Maharana·A. Melikyan
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Abstract

In this talk, we show how the monodromy matrix, ${\hat{\cal M}}$, can be constructed for the two dimensional tree level string effective action. The pole structure of ${\hat{\cal M}}$ 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, ${\hat{\cal M}}$ for the exactly solvable Nappi-Witten model, both when B=0 and $B\neq 0$, where these ideas can be directly checked.

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Ashok Das, J. Maharana, A. Melikyan. 2002-10-01. Monodromy, Duality and Integrability of Two Dimensional String Effective Action. https://arxiv.org/abs/hep-th/0210012

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