The Hubble tension in the non-flat Super-$\Lambda {\rm CDM}$ model

Abstract

We investigate the Hubble tension in the non-flat Super-$\Lambda {\rm CDM}$ model. The non-flat Super-$\Lambda {\rm CDM}$ model extends the Super-$\Lambda {\rm CDM}$ model by including the spatial curvature as a free parameter. The Super-$\Lambda {\rm CDM}$ model extends the standard $\Lambda {\rm CDM}$ model of cosmology through additional parameters accounting for the possible effect of a trispectrum in the primordial fluctuations. In the cosmic microwave background data, this effect can be parameterized using parameters that change the observed angular power spectrum from the theoretical power spectrum due to a trispectrum that couples long and short wavelength modes. In this work, we perform Markov Chain Monte Carlo (MCMC) data analysis on the recent Planck 2018 temperature and polarization fluctuations data and the local Hubble constant measurements from supernovae data assuming a non-flat Super-$\Lambda {\rm CDM}$ model. We find that there is a preference for non-zero values of the spatial curvature parameter $\Omega_k$ and the Super-$\Lambda {\rm CDM}$ parameter $A_0$ at a level of $\Delta \chi^2$ improvement of approximately 23.