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arXiv · 1605.04857

Testing CCDM Cosmology with the Radiation Temperature-Redshift Relation

I. Baranov·J. F. Jesus·J. A. S. Lima
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Abstract

The standard $\Lambda$CDM model can be mimicked at the background and perturbative levels (linear and non-linear) by a class of gravitationally induced particle production cosmology dubbed CCDM cosmology. However, the radiation component in the CCDM model follows a slightly different temperature-redshift $T(z)$-law which depends on an extra parameter, $\nu_r$, describing the subdominant photon production rate. Here we perform a statistical analysis based on a compilation of 36 recent measurements of $T(z)$ at low and intermediate redshifts. The likelihood of the production rate in CCDM cosmologies is constrained by $\nu_r = 0.024^{+0.026}_{-0.024}$ ($1\sigma$ confidence level), thereby showing that $\Lambda$CDM ($\nu_r=0$) is still compatible with the adopted data sample. Although being hardly differentiated in the dynamic sector (cosmic history and matter fluctuations), the so-called thermal sector (temperature law, abundances of thermal relics and CMB power spectrum) offers a clear possibility for crucial tests confronting $\Lambda$CDM and CCDM cosmologies.

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I. Baranov, J. F. Jesus, J. A. S. Lima. 2016-05-16. Testing CCDM Cosmology with the Radiation Temperature-Redshift Relation. https://doi.org/10.1007/s10714-019-2516-3

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