Double Field Theory of Type II Strings

Understand

We use double field theory to give a unified description of the low energy limits of type IIA and type IIB superstrings.

• The Ramond-Ramond potentials fit into spinor representations of the duality group O(D,D) and field-strengths are obtained by acting with the Dirac operator on the potentials.
• The action, supplemented by a Spin^+(D,D)-covariant self-duality condition on field strengths, reduces to the IIA and IIB theories in different frames.
• As usual, the NS-NS gravitational variables are described through the generalized metric.