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arXiv · 0906.1201

Relativistic Quantum Gravity at a Lifshitz Point

Cristiano Germani·Alex Kehagias·Konstadinos Sfetsos
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Abstract

We show that the Horava theory for the completion of General Relativity at UV scales can be interpreted as a gauge fixed theory, and it can be extended to an invariant theory under the full group of four-dimensional diffeomorphisms. In this respect, although being fully relativistic, it results to be locally anisotropic in the time-like and space-like directions defined by a family of irrotational observers. We show that this theory propagates generically three degrees of freedom: two of them are related to the four-dimensional diffeomorphism invariant graviton (the metric) and one is related to a propagating scalar mode. Finally, we note that in the present formulation, matter can be consistently coupled to gravity.

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Cristiano Germani, Alex Kehagias, Konstadinos Sfetsos. 2009-06-07. Relativistic Quantum Gravity at a Lifshitz Point. https://doi.org/10.1088/1126-6708/2009/09/060

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