Work

Is the w0waCDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck CMB anisotropy data?

Year: 2025

Type: article

Abstract: We study the performance of the spatially flat dynamical dark energy [Formula: see text]CDM parameterization, with redshift-dependent dark energy fluid equation of state parameter [Formula: see text], with and without a varying cosmic microwave background (CMB) lensing consistency parameter [Formula: see text], against Planck CMB data (P18 and lensing) and a combination of non-CMB data composed of baryonic acoustic oscillation (BAO) measurements that do not include DESI BAO data, Pantheon+ type Ia supernovae (SNIa) observations, Hubble parameter [[Formula: see text]] measurements and growth factor ([Formula: see text]) data points. From our most restrictive data set, P18+lensing+non-CMB, for the [Formula: see text]CDM+[Formula: see text] parameterization, we obtain [Formula: see text], [Formula: see text], the asymptotic limit [Formula: see text], and [Formula: see text] (all [Formula: see text] errors). This joint analysis of CMB and non-CMB data favors dark energy dynamics over a cosmological constant at [Formula: see text] and [Formula: see text] at [Formula: see text], i.e. more smoothing of the Planck CMB anisotropy data than is predicted by the best-fit model. For the [Formula: see text]CDM parameterization with [Formula: see text] the evidence in favor of dark energy dynamics is larger, [Formula: see text], suggesting that at least part of the evidence for dark energy dynamics comes from the excess smoothing of the Planck CMB anisotropy data. For the [Formula: see text]CDM parameterization with [Formula: see text], there is a difference of [Formula: see text] between P18 and non-CMB cosmological parameter constraints and [Formula: see text] between P18+lensing and non-CMB constraints. When [Formula: see text] is allowed to vary these tensions reduced to [Formula: see text] and [Formula: see text] respectively. Our P18+lensing+non-CMB data compilation positively favors the [Formula: see text]CDM parameterization without and with a varying [Formula: see text] parameter over the flat [Formula: see text]CDM model, and [Formula: see text]CDM+[Formula: see text] is also positively favored over [Formula: see text]CDM.

Source: International Journal of Modern Physics D

DOI: 10.1142/s0218271825500580

Authors: Chan-Gyung Park, Javier de Cruz Pérez, Bharat Ratra

Institutions: Jeonbuk National University, University of Córdoba, Kansas State University

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: European Commission, National Research Foundation, National Research Foundation of Korea, Ministry of Science and ICT, South Korea

Award: G8960860873