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arXiv · 1307.8377

Covariant action for a string in doubled yet gauged spacetime

Kanghoon Lee·Jeong-Hyuck Park
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Abstract

The section condition in double field theory has been shown to imply that a physical point should be one-to-one identified with a gauge orbit in the doubled coordinate space. Here we show the converse is also true, and continue to explore the idea of `spacetime being doubled yet gauged'. Introducing an appropriate gauge connection, we construct a string action, with an arbitrary generalized metric, which is completely covariant with respect to the coordinate gauge symmetry, generalized diffeomorphisms, world-sheet diffeomorphisms, world-sheet Weyl symmetry and O(D,D) T-duality. A topological term previously proposed in the literature naturally arises and a self-duality condition follows from the equations of motion. Further, the action may couple to a T-dual background where the Riemannian metric becomes everywhere singular.

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Kanghoon Lee, Jeong-Hyuck Park. 2014-01-07. Covariant action for a string in doubled yet gauged spacetime. https://doi.org/10.1016/j.nuclphysb.2014.01.003

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