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arXiv · hep-th/0609222

Lorentz violation in the linearized gravity

A. F. Ferrari·M. Gomes·J. R. Nascimento·E. Passos·A. Yu. Petrov·A. J. da Silva
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Abstract

We study some physical consequences of the introduction of a Lorentz-violating modification term in the linearized gravity, which leads to modified dispersion relations for gravitational waves in the vacuum. We discuss two possible mechanisms for the induction of such a term in the Lagrangian. First, it is generated at the quantum level by a Lorentz-breaking coupling of the gravity field to a spinor field. Second, it appears as consequence of a particular modification of the Poisson algebra of the canonical variables, in the spirit of the so-called ``noncommutative fields approach''.

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A. F. Ferrari, M. Gomes, J. R. Nascimento, E. Passos, A. Yu. Petrov, A. J. da Silva. 2007-08-30. Lorentz violation in the linearized gravity. https://doi.org/10.1016/j.physletb.2007.07.013

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