Courant bracket found out to be T-dual to Roytenberg bracket

Abstract: Bosonic string moving in coordinate dependent background fields is considered. We calculate the generalized currents Poisson bracket algebra and find that it gives rise to the Courant bracket. Furthermore, we consider the T-dual theory and obtain the dual generalized currents Poisson bracket algebra. It gives rise to the Roytenberg bracket. We conclude that the Courant bracket twisted with the Kalb-Ramond field is T-dual to the Roytenberg bracket, with $Q$ and $R$ flux.