T-duality and alpha' corrections

DIEGO MARQUES; CARMEN NÚÑEZ

JOURNAL OF HIGH ENERGY PHYSICS

SPRINGER

Lugar: Berlin; Año: 2015 vol. 2015 p. 1 - 27

1126-6708

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 four-derivative terms that are even and odd with respect to a Z2-parity transformation that changes the sign of the two-form field. The Z2-symmetric model reproduces the closed bosonic string, and the heterotic string effective action is obtained through a Z2-parity-breaking choice of parameters. The theory is an extension of the generalized frame formulation of Double Field Theory, in which the gauge transformations are deformed by a first-order generalized Green-Schwarz transformation. This deformation defines a duality covariant gauge principle that requires and fixes the fourderivative terms. We discuss the O(d, d) structure of the theory and the (non-)covariance of the required field redefinitions.