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Metric Redefinitions in Einstein-Aether Theory

Brendan Z. Foster
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Abstract

`Einstein-Aether' theory, in which gravity couples to a dynamical, time-like, unit-norm vector field, provides a means for studying Lorentz violation in a generally covariant setting. Demonstrated here is the effect of a redefinition of the metric and vector field in terms of the original fields and two free parameters. The net effect is a change of the coupling constants appearing in the action. Using such a redefinition, one of the coupling constants can be set to zero, simplifying studies of solutions of the theory.

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Brendan Z. Foster. 2005-08-01. Metric Redefinitions in Einstein-Aether Theory. https://doi.org/10.1103/physrevd.72.044017

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