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arXiv · 1405.6351

Comment on "Scalar Einstein-Aether theory"

Ted Jacobson·Antony J. Speranza
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Abstract

A recent paper studies a modification of Einstein-aether theory in which the aether vector is restricted, at the level of the action, to be the gradient of a scalar. In this comment we note that this scalar version of Einstein-aether theory is equivalent to the projectable version of the IR limit of Hořava gravity when the potential for the scalar is constant. This provides a generally covariant formulation for projectable Hořava gravity.

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Ted Jacobson, Antony J. Speranza. 2014-06-12. Comment on "Scalar Einstein-Aether theory". https://arxiv.org/abs/1405.6351

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