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arXiv · hep-th/9905036

T-Duality Can Fail

Paul S. Aspinwall·M. Ronen Plesser
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Abstract

We show that T-duality can be broken by nonperturbative effects in string coupling. The T-duality in question is that of the 2-torus when the heterotic string is compactified on K3 x T2. This case is compared carefully to a situation where T-duality appears to work. A holonomy argument is presented to show that T-dualities (and general U-dualities) should only be expected for large amounts of supersymmetry. This breaking of R <-> 1/R symmetry raises some interesting questions in string theory which we discuss. Finally we discuss how the classical modular group of a 2-torus appears to be broken too.

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Paul S. Aspinwall, M. Ronen Plesser. 1999-05-05. T-Duality Can Fail. https://doi.org/10.1088/1126-6708%2F1999%2F08%2F001

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