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arXiv · 2005.04131

Bayesian Comparison of the Cosmic Duality Scenarios

W. J. C. da Silva·R. F. L. Holanda·R. Silva
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Abstract

The cosmic distance duality relation (CDDR), $D_{\rm L}(1+z)^{-2}/D_{\rm A}=\eta=1$, with $D_{\rm L}$ and $D_{\rm A}$, being the luminosity and angular diameter distances, respectively, is a crucial premise in cosmological scenarios. Many investigations try to test CDDR through observational approaches, even some of these ones also consider a deformed CDDR, i.e., $\eta=\eta(z)$. In this paper, we use type Ia supernovae luminosity distances and galaxy cluster measurements (their angular diameter distances and gas mass fractions) in order to perform a Bayesian model comparison between $ \eta(z) $ functions. We show that the data here used are unable to pinpoint, with a high degree of Bayesian evidence, which $\eta(z)$ function best captures the evolution of CDDR.

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W. J. C. da Silva, R. F. L. Holanda, R. Silva. 2020-05-08. Bayesian Comparison of the Cosmic Duality Scenarios. https://doi.org/10.1103/physrevd.102.063513

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