An O(D,D) Invariant Hamiltonian Action for the Superstring

TL;DR

This paper develops an O(D,D) invariant Hamiltonian framework for bosonic and superstrings, integrating double field theory concepts and T-duality as a canonical transformation, with a focus on the algebra of constraints and the section condition.

Contribution

It introduces a Hamiltonian approach to superstring theory that makes T-duality manifest and incorporates double field theory structures.

Findings

O(D,D) invariant actions constructed for bosonic and superstrings

T-duality realized as a canonical transformation in phase space

Closure of the constraint algebra leads to the section condition

Abstract

We construct O(D,D) invariant actions for the bosonic string and RNS superstring, using Hamiltonian methods and ideas from double field theory. In this framework the doubled coordinates of double field theory appear as coordinates on phase space and T-duality becomes a canonical transformation. Requiring the algebra of constraints to close leads to the section condition, which splits the phase space coordinates into spacetime coordinates and momenta.