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arXiv · 1602.07705

Towards a world-sheet description of doubled geometry in string theory

Ioannis Bakas·Dieter Lust·Erik Plauschinn
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Abstract

Starting from a sigma-model for a doubled target-space geometry, we show that the number of target-space dimensions can be reduced by half through a gauging procedure. We apply this formalism to a class of backgrounds relevant for double field theory, and illustrate how choosing different gaugings leads to string-theory configurations T-dual to each other. We furthermore discuss that given a conformal doubled theory, the reduced theories are conformal as well. As an example we consider the three-dimensional SU(2) WZW model and show that the only possible reduced backgrounds are the cigar and trumpet CFTs in two dimensions, which are indeed T-dual to each other.

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Ioannis Bakas, Dieter Lust, Erik Plauschinn. 2016-03-08. Towards a world-sheet description of doubled geometry in string theory. https://doi.org/10.1002/prop.201600085

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