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arXiv · 1802.02255

Model Selection Using Cosmic Chronometers with Gaussian Processes

Fulvio Melia·Manoj K. Yennapureddy
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Abstract

The use of Gaussian Processes with a measurement of the cosmic expansion rate based solely on the observation of cosmic chronometers provides a completely cosmology-independent reconstruction of the Hubble constant H(z) suitable for testing different models. The corresponding dispersion sigma_H is smaller than ~9% over the entire redshift range (0 < z < 2) of the observations, rivaling many kinds of cosmological measurements available today. We use the reconstructed H(z) function to test six different cosmologies, and show that it favours the R_h=ct universe, which has only one free parameter (i.e., H_0) over other models, including Planck LCDM. The parameters of the standard model may be re-optimized to improve the fits to the reconstructed H(z) function, but the results have smaller p-values than one finds with R_h=ct.

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Fulvio Melia, Manoj K. Yennapureddy. 2018-02-06. Model Selection Using Cosmic Chronometers with Gaussian Processes. https://doi.org/10.1088/1475-7516%2F2018%2F02%2F034

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