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arXiv · 1809.02340

Can the $H_0$ tension be resolved in extensions to $\Lambda$CDM cosmology?

Rui-Yun Guo·Jing-Fei Zhang·Xin Zhang
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Abstract

We wish to investigate whether there is an extension to the base $\Lambda$CDM cosmology that can resolve the tension between the Planck observation of the cosmic microwave background anisotropies and the local measurement of the Hubble constant. We consider various plausible extended models in this work, and we use the Planck 2015 observation, combined with the baryon acoustic oscillation data, the JLA type Ia supernovae data, and the local measurement of the Hubble constant (by Riess et al. in 2016), to make an analysis. We find that the holographic dark energy plus sterile neutrino model can reduce the tension to be at the 1.11$\sigma$ level, but this model is obviously not favored by the current observations. Among these extended models, the $\Lambda$CDM+$N_{\rm eff}$ model is most favored by the current observations, and this model can reduce the tension to be at the 1.87$\sigma$ level. By a careful test, we conclude that none of these extended models can convincingly resolve the $H_0$ tension.

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Rui-Yun Guo, Jing-Fei Zhang, Xin Zhang. 2018-09-07. Can the $H_0$ tension be resolved in extensions to $\Lambda$CDM cosmology?. https://doi.org/10.1088/1475-7516%2F2019%2F02%2F054

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