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arXiv · 2012.14377

CMB lensing in a modified $\Lambda$CDM model in light of the $H_0$ tension

Hossein Moshafi·Shant Baghram·Nima Khosravi
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Abstract

The observed discrepancy of the Hubble parameter measurements in the local universe with the cosmic microwave background (CMB) data may indicate a new physics. It is vital to test the alternative models that reconcile the Hubble tension with other cosmological observations in this direction. The CMB lensing is a crucial observation that relates the early universe perturbations to the matter's late-time distribution. In this work, we study the prediction of the \"u$\Lambda$CDM as a solution for $H_0$ tension for CMB lensing and the low- and high-$\ell$'s temperature (TT) power spectrum internal inconsistency. We show that this model relaxes the low- and high-$\ell$'s TT mild inconsistency and the CMB lensing tensions simultaneously. Accordingly, \"u$\Lambda$CDM having the same number of free parameters as $\Lambda$CDM with lensing amplitude $A_L$ added, has a better fit with $\Delta \chi^2=-3.3$.

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Hossein Moshafi, Shant Baghram, Nima Khosravi. 2020-12-28. CMB lensing in a modified $\Lambda$CDM model in light of the $H_0$ tension. https://doi.org/10.1103/physrevd.104.063506

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