Aspects of the Doubled Worldsheet

TL;DR

This paper clarifies the relationships between different T-duality symmetric string formulations, introduces a covariant doubled string approach, and extends the formalism to non-Abelian T-duality and supersymmetric cases.

Contribution

It provides a detailed derivation of the PST covariant doubled string from gauge fixing, explores the role of spectator fields, and develops a supersymmetric duality invariant formalism.

Findings

Derived the PST covariant doubled string from gauge fixing.

Showed how the doubled dilaton emerges naturally.

Extended the formalism to non-Abelian T-duality and supersymmetry.

Abstract

We clarify the relation between various approaches to the manifestly T-duality symmetric string. We explain in detail how the PST covariant doubled string arises from an unusual gauge fixing. We pay careful attention to the role of "spectator" fields in this process and also show how the T-duality invariant doubled dilaton emerges naturally. We extend these ideas to non-Abelian T-duality and show they give rise to the duality invariant formalism based on the semi-Abelian Drinfeld Double. We then develop the N=(0,1) supersymmetric duality invariant formalism.