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arXiv · 1310.5115

Undoing the twist: the Hořava limit of Einstein-aether

Ted Jacobson
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Abstract

We show that Hořava gravity can be obtained from Einstein-aether theory in the limit that the twist coupling constant goes to infinity, while holding fixed the expansion, shear and acceleration couplings. This limit helps to clarify the relation between the two theories, and allows Hořava results to be obtained from Einstein-aether ones. The limit is illustrated with several examples, including rotating black hole equations, PPN parameters, and radiation rates from binary systems.

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Ted Jacobson. 2014-03-23. Undoing the twist: the Hořava limit of Einstein-aether. https://doi.org/10.1103/physrevd.89.081501

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