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arXiv · 1511.04335

Sub-percent constraints on cosmological temperature evolution

A. Avgoustidis·R. T. Génova-Santos·G. Luzzi·C. J. A. P. Martins
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Abstract

The redshift dependence of the cosmic microwave background temperature is one of the key cosmological observables. In the standard cosmological model one has $T(z)=T_0(1+z)$, where $T_0$ is the present-day temperature. Deviations from this behavior would imply the presence of new physics. Here we discuss how the combination of all currently available direct and indirect measurements of $T(z)$ constrains the common phenomenological parametrization $T(z)=T_0(1+z)^{1-β}$, and obtain the first sub-percent constraint on the $β$ parameter, specifically $β=(7.6\pm8.0)\times10^{-3}$ at the $68.3\%$ confidence level.

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A. Avgoustidis, R. T. Génova-Santos, G. Luzzi, C. J. A. P. Martins. 2015-11-13. Sub-percent constraints on cosmological temperature evolution. https://doi.org/10.1103/physrevd.93.043521

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