Superspace formulations of the (super)twistor string

TL;DR

This paper explores superspace formulations of twistor string models, linking tensionless superstrings to twistor strings and discussing potential tensionful superstring actions and higher-dimensional extensions within superspace frameworks.

Contribution

It provides a superspace formulation for the Berkovits-Siegel twistor string and investigates inverse transforms and higher-dimensional generalizations.

Findings

Superspace formulation for the Berkovits-Siegel twistor string established.

Inverse twistor transform yields a dynamical system with dual superspace coordinates.

Discussion of candidate tensionful superstring actions and higher-dimensional twistor string extensions.

Abstract

The superspace formulation of the worldvolume action of twistor string models is considered. It is shown that for the Berkovits-Siegel closed twistor string such a formulation is provided by a N=4 twistor-like action of the tensionless superstring. A similar inverse twistor transform of the open twistor string model (Berkovits model) results in a dynamical system containing two copies of the D=4, N=4 superspace coordinate functions, one left-moving and one right-moving, that are glued by the boundary conditions. We also discuss possible candidates for a tensionful superstring action leading to the twistor string in the tensionless limit as well as multidimensional counterparts of twistor strings in the framework of both `standard' superspace and superspace enlarged by tensorial coordinates (tensorial superspaces), which constitute a natural framework for massless higher spin theories.