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arXiv · 0902.4032

Non-geometric backgrounds, doubled geometry and generalised T-duality

C. M. Hull·R. A. Reid-Edwards
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Abstract

String backgrounds with a local torus fibration such as T-folds are naturally formulated in a doubled formalism in which the torus fibres are doubled to include dual coordinates conjugate to winding number. Here we formulate and explore a generalisation of this construction in which all coordinates are doubled, so that the doubled space is a twisted torus, i.e. a compact space constructed from identifying a group manifold under a discrete subgroup. This incorporates reductions with duality twists, T-folds and a class of flux compactifications, together with the non-geometric backgrounds expected to arise from these through T-duality. It also incorporates backgrounds that are not even locally geometric, and suggests a generalisation of T-duality to a more general context. We discuss the effective field theory arising from such an internal sector, give a world-sheet sigma model formulation of string theory on such backgrounds and illustrate our discussion with detailed examples.

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C. M. Hull, R. A. Reid-Edwards. 2009-02-23. Non-geometric backgrounds, doubled geometry and generalised T-duality. https://doi.org/10.1088/1126-6708/2009/09/014

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