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arXiv · 1512.07854

Linearized gravity with matter time

Masooma Ali·Viqar Husain·Shohreh Rahmati·Jonathan Ziprick
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Abstract

We study general relativity with pressureless dust in the canonical formulation, with the dust field chosen as a matter-time gauge. The resulting theory has three physical degrees of freedom in the metric field. The linearized canonical theory reveals two graviton modes and a scalar mode. We find that the graviton modes remain Lorentz covariant despite the time gauge, and that the scalar mode is ultralocal. We discuss also a modification of the theory to include a parameter in the Hamiltonian analogous to that in Horava-Lifshitz models. In this case the scalar mode is no longer ultralocal, and acquires a propagation speed dependent on the deformation parameter.

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Masooma Ali, Viqar Husain, Shohreh Rahmati, Jonathan Ziprick. 2016-01-05. Linearized gravity with matter time. https://doi.org/10.1088/0264-9381%2F33%2F10%2F105012

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