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arXiv · 1304.5946

Comments on double field theory and diffeomorphisms

Jeong-Hyuck Park
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Abstract

As the theory is subject to a section condition, coordinates in double field theory do not represent physical points in an injective manner. We argue that a physical point should be rather one-to-one identified with a `gauge orbit' in the coordinate space. The diffeomorphism symmetry then implies an invariance under arbitrary reparametrizations of the gauge orbits. Within this generalized sense of diffeomorphism, we show that a recently proposed tensorial transformation rule for finite coordinate transformations is actually (i) consistent with the standard exponential map, and further (ii) compatible with the full covariance of the `semi-covariant' derivatives and curvatures after projectors are properly imposed.

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Jeong-Hyuck Park. 2013-04-22. Comments on double field theory and diffeomorphisms. https://doi.org/10.1007/jhep06(2013)098

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