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arXiv · 1507.00652

T-duality and $α'$-corrections

Diego Marques·Carmen A. Nunez
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Abstract

We construct an $O(d,d)$ invariant universal formulation of the first-order $α'$-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 $Z_2$-parity transformation that changes the sign of the two-form field. The $Z_2$-symmetric model reproduces the closed bosonic string, and the heterotic string effective action is obtained through a $Z_2$-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 four-derivative terms. We discuss the $O(d,d)$ structure of the theory and the (non-)covariance of the required field redefinitions.

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Diego Marques, Carmen A. Nunez. 2015-12-23. T-duality and $α'$-corrections. https://doi.org/10.1007/jhep10(2015)084

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