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arXiv · 1509.04983

Cosmology in $(1+1)$-dimensional Hořava-Lifshitz theory of gravity

J. P. M. Pitelli
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Abstract

The $(1+1)$-dimensional Friedmann-Robertson-Walker (FRW) universe filled with a perfect fluid with equation of state $p=ωρ$ is analyzed through the view of Ho\v rava-Lifshitz (HL) theory of gravity. In this theory, the anisotropic scaling of space and time breaks Lorentz invariance of General Relativity (GR) in such a way that the gravitational action is no longer a topological invariant and the theory becomes dynamical. With the introduction of a perfect fluid through Schutz formalism, it is shown that the resulting dynamical theory is very similar to the two-dimensional Jackiw-Teitelboim (JT) model, where a dilatonic degree of freedom is introduced to force a dynamical theory. However, in HL theory, the introduction of a dilaton field is not necessary.

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J. P. M. Pitelli. 2015-09-16. Cosmology in $(1+1)$-dimensional Hořava-Lifshitz theory of gravity. https://doi.org/10.1103/physrevd.92.084012

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