We study the effects of multiple transitions in the vacuum dark energy density on the H0 tension problem. We consider a phenomenological model in which the vacuum energy density undergoes multiple transitions in the early as well as the late universe and compare the model's predictions using the three sets of data from CMB+BAO+SN. The transient dark energy can be either positive (dS-like) or negative (AdS-like). We conclude that a transient late-time AdS-type vacuum energy typically yields the higher value of H0 which can alleviate the H0 tension. In addition, to obtain a value of H0 comparable to the value obtained from the local cosmological measurements the spectral index ns moves towards its Harrison-Zel'dovich scale invariant value
@article{arxiv.2208.05583,
title = {Multiple transitions in vacuum dark energy and $H_0$ tension},
author = {Hossein Moshafi and Hassan Firouzjahi and Alireza Talebian},
journal= {arXiv preprint arXiv:2208.05583},
year = {2024}
}