Higher-derivative interactions and transformation rules of the fields in the effective field theories of the massless string states are strongly constrained by space-time symmetries and dualities. Here we use an exact ...

We construct an O(d, d) invariant universal formulation of the first-order alpha-prime-corrections of the string effective actions involving the dilaton, metric and two-form fields. Two free parameters interpolate between ...

We define a nonabelian version of particle-vortex duality, by dimensionally extending usual (1+1)-dimensional nonabelian T-duality to (2+1) dimensions. While we will explicitly describe a global SU(2) symmetry, our methods ...

Witten has recently proposed a string theory in twistor space whose D-instanton contributions are conjectured to compute M = 4 super-Yang-Mills scattering amplitudes. An alternative string theory in twistor space was then ...

In the last chapter, we considered T-duality for closed strings. Now we start off by considering T-duality for open strings, and see that it will lead to D-branes. Then, we define the low energy supergravity limits of ...

In this note we study the preservation of the classical pure spinor BRST constraints under super T-duality transformations. We also determine the invariance of the one-loop conformal invariance and of the local gauge and ...

There are two main approaches to duality covariant first order higher derivative corrections to the heterotic string, one extending the duality structure and the other deforming the gauge transformations. In this paper we ...

: We construct the effective action for toroidal compactifications of bosonicstring theory from generalized Scherk-Schwarz reductions of double field theory. The enhancedgauge symmetry arising at special points in moduli ...