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arXiv · hep-th/9705193

Duality Beyond the First Loop

Nemanja Kaloper·Krzysztof Meissner
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Abstract

In this article we give a calculation of the two-loop $σ$-model corrections to the T-duality map in string theory. We use the effective action approach, and analyze two-loop corrections in a specific subtraction scheme. Focusing on backgrounds which have a single Abelian isometry, we find the explicit form for the $O(α')$ modifications of the lowest order duality transformations. Rather surprisingly, the manifest two-loop duality depends crucially on the torsion field. In contrast to the dilaton and metric fields, which are merely passive spectators, the torsion plays a more active role, because of the anomalous couplings to the gauge fields that arise via dimensional reduction. Our results support the interpretation of T-duality as an expansion in the inverse string tension $α'$, and its order-by-order realization as a manifest symmetry of the full string theory.

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Nemanja Kaloper, Krzysztof Meissner. 1997-06-17. Duality Beyond the First Loop. https://doi.org/10.1103/physrevd.56.7940

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