Generalized Metric Formulation of Double Field Theory on Group Manifolds

We rewrite the recently derived cubic action of Double Field Theory on group manifolds [1] in terms of a generalized metric and extrapolate it to all orders in the fields. For the resulting action, we derive the field equations and state them in terms of a generalized curvature scalar and a generalized Ricci tensor. Compared to the generalized metric formulation of DFT derived from tori, all these quantities receive additional contributions related to the non-trivial background. It is shown that the action is invariant under its generalized diffeomorphisms and 2D-diffeomorphisms. Imposing additional constraints relating the background and fluctuations around it, the precise relation between the proposed generalized metric formulation of DFTWZW and of original DFT from tori is clarified. Furthermore, we show how to relate DFTWZW of the WZW background with the flux formulation of original DFT. ar X iv :1 50 2. 02 42 8v 3 [ he pth ] 1 6 Ju n 20 15