An invitation to Poisson-Lie T-duality in Double Field Theory and its applications

Abstract

Poisson-Lie (PL) T-duality has received much attention over the last five years in connection with integrable string worldsheet theories. At the level of the worldsheet, the algebraic structure underpinning these connections is made manifest with the $\mathcal{E}$-model, a first order Hamiltonian description of the string. The $\mathcal{E}$-model shares many similarities with Double Field Theory (DFT). We report on recent progress in establishing a precise linkage with DFT as the target space description of the $\mathcal{E}$-model. There are three important outcomes of this endeavor: 1) PL symmetry is made manifest at the level of (generalized) supergravity in DFT. 2) PL symmetric target spaces are described by a set of generalized frame fields that encode consistent truncations of supergravity. 3) PL dualisation rules are made explicit and are readily extended to include the R/R sector of the type II theory. These general results are put into context with their application to the the integrable Yang-Baxter model ($\eta$-deformation). This extended proceedings provides some introductory review of PL and an orientation to the results of arXiv:1707.08624 and arXiv:1810.11446.