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arXiv · 1808.07145

Data Analysis and Phenomenological Cosmology

Alan A. Coley·Beethoven Santos·Viraj A A Sanghai
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Abstract

In the era of precision cosmology, even percentage level effects are significant on cosmological observables. The recent tension between the local and global values of $H_0$ is much more significant than this, and any possible solution might rely on us going beyond the standard $Λ$CDM cosmological model. For much smaller, yet potentially significant effects, spatial curvature from averaging and cosmological backreaction on observational predictions could play a role. This is especially true with the higher precision of new observational data and improved statistical techniques. In this paper, we discuss the observational viability of a class of physically motivated cosmologies which can be parametrized by a phenomenological two-scale backreaction model with decoupled spatial curvature parameters and two Hubble scales. Using the latest JLA Supernovae data together with some of the latest BAO data, we perform a Bayesian model selection analysis and find that the phenomenological models are not favoured over the standard $Λ$CDM cosmological model. Although there is still a preference for non-zero and unequal dynamic and geometric spatial curvatures, there is little evidence for differing Hubble scales within these phenomenological template models.

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Alan A. Coley, Beethoven Santos, Viraj A A Sanghai. 2018-09-06. Data Analysis and Phenomenological Cosmology. https://doi.org/10.1088/1475-7516%2F2019%2F05%2F039

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