2021/01/31 by Li-Yang Gao, Ze-Wei Zhao, She-Sheng Xue +1 · 3 citations
Physics and Astronomy · #astro-ph.CO #gr-qc #hep-ph
paper · pdf · doi:10.1088/1475-7516/2021/07/005
published as JCAP 07 (2021) 005 · 17 pages, 6 figures; accepted for publication in JCAP
arxiv created 2021/05/26 · arxiv updated 2021/07/07
We investigate an extended cosmological model motivated by the asymptotic safety of gravitational field theory, in which the matter and radiation densities and the cosmological constant receive a correction parametrized by the parameters δG and δΛ, leading to that both the evolutions of the matter and radiation densities and the cosmological constant slightly deviate from the standard forms. Here we explain this model as a scenario of vacuum energy interacting with matter and radiation. We consider two cases of the model: (i) ΛCDM with one additional free parameter δG, with δ\rm G and δΛ related by a low-redshift limit relation and (ii) eΛCDM with two additional free parameters δG and δΛ that are independent of each other. We use two data combinations, CMB+BAO+SN (CBS) and CMB+BAO+SN+H0 (CBSH), to constrain the models. We find that, in the case of using the CBS data, neither ΛCDM nor eΛCDM can effectively alleviate the H0 tension. However, it is found that using the CBSH data the H0 tension can be greatly relieved by the models. In particular, in the case of eΛCDM, the H0 tension can be resolved to 0.71σ. We conclude that as an interacting dark energy model, ΛCDM is much better than Λ(t)CDM in the sense of both relieving the H0 tension and fitting to the current observational data.