Doubled \alpha'-Geometry

Understand

We develop doubled-coordinate field theory to determine the \alpha' corrections to the massless sector of oriented bosonic closed string theory.

• Our key tool is a string current algebra of free left-handed bosons that makes O(D,D) T-duality manifest.
• While T-dualities are unchanged, diffeomorphisms and b-field gauge transformations receive corrections, with a gauge algebra given by an \alpha'-deformation of the duality-covariantized Courant bracket.
• The action is cubic in a double metric field, an unconstrained extension of the generalized metric that encodes the gravitational fields.