# Type II DFT solutions from Poisson-Lie T-duality/plurality

## TL;DR

This paper explores the generalization of T-duality in string theory through Poisson-Lie T-plurality, utilizing double field theory to formulate duality transformations and resolve existing puzzles, with applications to AdS5×S5.

## Contribution

It formulates Poisson-Lie T-plurality as an O(n,n) transformation within double field theory, extending non-Abelian T-duality and addressing the dilaton puzzle.

## Key findings

- Poisson-Lie T-plurality described as an O(n,n) transformation.
- Covariance of DFT equations of motion demonstrated.
- Resolution of the dilaton puzzle in PL T-plurality.

## Abstract

String theory has the T-duality symmetry when the target space has Abelian isometries. A generalization of the T-duality, where the isometry group is non-Abelian, is known as the non-Abelian T-duality, which works well as a solution-generating technique in supergravity. In this paper, we describe the non-Abelian T-duality as a kind of O(D,D) transformation when the isometry group acts without isotropy. We then provide a duality transformation rule for the Ramond-Ramond fields by using the technique of double field theory (DFT). We also study a more general class of solution-generating technique, the Poisson-Lie (PL) T-duality or T-plurality. We describe the PL T-plurality as an O(n,n) transformation and clearly show the covariance of the DFT equations of motion by using the gauged DFT. We further discuss the PL T-plurality with spectator fields, and study an application to the AdS$_5\times$S$^5$ solution. The dilaton puzzle known in the context of the PL T-plurality is resolved with the help of DFT.