T-duality revisited

Understand

We revisit the transformation rules of the metric and Kalb-Ramond field under T-duality, and express the corresponding relations in terms of the metric G and the field strength H=dB.

• In the course of the derivation, we find an explanation for potential reductions of the isometry group in the dual background.
• The formalism employed in this paper is illustrated with examples based on tori and spheres, where for the latter we construct a new non-geometric background.