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arXiv · 1803.03615

Hořava-Lifshitz cosmology in light of new data

Nils A. Nilsson·Ewa Czuchry
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Abstract

We present new observational constraints on Lorentz violating Hořava-Lifshitz cosmological scenarios using an updated cosmological data set from Cosmic Microwave Background (Planck CMB), expansion rates of elliptical and lenticular galaxies, JLA compilation (Joint Light-Curve Analysis) data for Type Ia supernovae (SneIa), Baryon Acoustic Oscillations (BAO) and priors on the Hubble parameter with an alternative parametrisation of the equations. Unlike in other approaches we consider the curvature parameter $Ω_k$ as a free parameter in the analysis we considered the parameters $Ω_k$ and $ΔN_ν$ as completely free, which helped to place new, updated bounds on several of the theory parameters. Remarkably, the detailed balance scenario exhibits positive spatial curvature to more than 3$σ$, whereas for further theory generalizations we found evidence for positive spatial curvature at 1$σ$. This could create circumstantial evidence from observations and could be used to single out distinct formulations and scenarios.

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BibTeXRIS

Nils A. Nilsson, Ewa Czuchry. 2018-12-28. Hořava-Lifshitz cosmology in light of new data. https://doi.org/10.1016/j.dark.2018.100253

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