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We do not solve tensions with concordance cosmology; we do obtain $H_0approx 74,$km/s/Mpc from CMB+BAO+SN data in our model, but that is not the point. Discrepancies in Hubble constant values obtained by various astrophysical probes should not be viewed in isolation. While one can resolve at least some of the differences through either an early time transition or late time transition in the expansion rate, these introduce other changes. We advocate a holistic approach, using a wide variety of cosmic data, rather than focusing on one number, $H_0$. Vacuum metamorphosis, a late time transition physically motivated by quantum gravitational effects and with the same number of parameters as lcdm, can successfully give a high $H_0$ value from cosmic microwave background data but fails when combined with multiple distance probes. We also explore the influence of spatial curvature, and of a conjoined analysis of cosmic expansion and growth.
With the entrance of cosmology in its new era of high precision experiments, low- and high-redshift observations set off tensions in the measurements of both the present-day expansion rate ($H_0$) and the clustering of matter ($S_8$). We provide a si
The cosmological term, $Lambda$, was introduced $104$ years ago by Einstein in his gravitational field equations. Whether $Lambda$ is a rigid quantity or a dynamical variable in cosmology has been a matter of debate for many years, especially after t
We investigate the $H_0$ tension in a range of extended model frameworks beyond the standard $Lambda$CDM without the data from cosmic microwave background (CMB). Specifically, we adopt the data from baryon acoustic oscillation, big bang nucleosynthes
Phantom dark energy can produce amplified cosmic acceleration at late times, thus increasing the value of $H_0$ favored by CMB data and releasing the tension with local measurements of $H_0$. We show that the best fit value of $H_0$ in the context of
In this letter we propose a reduction of the $H_0$ tension puzzle by means of a theory of minimally modified gravity which is dubbed VCDM. After confronting the theory with the experiments, we find that the data allow for a low-redshift transition in