Inflationary potential as seen from different angles: model compatibility from multiple CMB missions

• Published in: Journal of Cosmology and Astroparticle Physics
• Main Authors: Giarè, William, Pan, Supriya, Di Valentino, Eleonora, Yang, Weiqiang, Haro Cases, Jaume, Melchiorri, Alessandro
• Other Authors: Universitat Politècnica de Catalunya. Departament de Matemàtiques
• Format: Article in Journal/Newspaper
• Language: English
• Published: IOP Publishing 2023
• Subjects: Àrees temàtiques de la UPC::Física::Astronomia i astrofísica::Cosmologia i cosmogonia; Cosmology; Gravitational waves; Inflation; Inflation and CMBR theory; Physics of the early universe; Cosmologia; Ones gravitacionals; South pole
• Online Access: http://hdl.handle.net/2117/395453; https://arxiv.org/abs/2305.15378; https://doi.org/10.1088/1475-7516/2023/09/019

The cosmic microwave background (CMB) temperature and polarization anisotropies, as observed by independent astronomical missions such as WMAP, Planck, and most recently the Atacama Cosmology Telescope and the South Pole Telescope have played a vital role in accurately constraining cosmological theories and models, establishing cosmic inflation as the most widely accepted theory for describing the physics of the early Universe. However, the absence of a definitive detection of B-mode polarization and the emerging discrepancies among different CMB experiments present a challenge in determining which inflationary models best explain the observed data. In this work, we further explore this difficulty and conduct a case study by analyzing four well-known inflationary potentials in light of the latest CMB temperature and polarization anisotropy measurements and lensing data released by the Planck satellite and the Atacama Cosmology Telescope. Additionally, we incorporate B-modes polarization data from the BICEP/Keck Collaboration, as well as Baryon Acoustic Oscillations and Redshift Space Distortions measurements from BOSS DR12 and eBOSS DR16. We show that the most typical models such as Starobinsky and a-attractors are in disagreement with the Atacama Cosmology Telescope small-scale CMB measurements, particularly when combined with B-modes polarization data. On the other hand, these potentials are in perfect agreement with the Planck measurements at larger angular scales. This dichotomy makes it challenging to identify a single model or a group of models that can be universally considered as the preferred choice based on all available CMB observations. "JdH is supported by the Spanish grant PID2021-123903NB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDFA way of making Europe”" Peer Reviewed Postprint (published version)