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The use of luminous red galaxies as cosmic chronometers provides us with an indispensable method of measuring the universal expansion rate H (z) in a model-independent way. Unlike many probes of the cosmological history, this approach does not rely on integrated quantities, such as the luminosity distance, and therefore does not require the pre-assumption of any particular model, which may bias subsequent interpretations of the data. We employ three statistical tools -- the Akaike, Kullback, and Bayes Information Criteria (AIC, KIC and BIC) -- to compare the LCDM model and the Rₕ=ct Universe with the currently available measurements of H (z), and show that the Rₕ=ct Universe is favored by these model selection criteria. The parameters in each model are individually optimized by maximum likelihood estimation. The Rₕ=ct Universe fits the data with a reduced chi²dof=0. 745 for a Hubble constant H₀=63. 2+/-2. 5 km/s/Mpc, and H₀ is the sole parameter in this model. By comparison, the optimal LCDM model, which has three free parameters (including H₀=68. 9+/-2. 4 km/s/Mpc, Omegaₘ=0. 32, and a dark-energy equation of state pde=-rhode), fits the H (z) data with a reduced chi²dof=0. 777. With these chi²dof values, the AIC yields a likelihood of about 82 per cent that the distance--redshift relation of the Rₕ=ct Universe is closer to the correct cosmology, than is the case for LCDM. If the alternative BIC criterion is used, the respective Bayesian posterior probabilities are 91. 2 per cent (Rₕ=ct) versus 8. 8 per cent (LCDM). Using the concordance LCDM parameter values, rather than those obtained by fitting LCDM to the cosmic chronometer data, would further disfavor LCDM.
Melia et al. (Fri,) studied this question.