{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/improved-planck-constraints-on-axion-like","title":"Improved Planck constraints on axion-like early dark energy as a resolution of the Hubble tension","arxiv_id":"2311.00524","date":"2023-11-01","proceeding":null,"authors":["George Efstathiou","Erik Rosenberg","Vivian Poulin"],"abstract":"Axion-like early dark energy (EDE) as an extension to $\\Lambda$CDM has been proposed as a possible solution to the 'Hubble tension'. We revisit this model using a new cosmic microwave background (CMB) temperature and polarization likelihood constructed from the {\\it Planck} NPIPE data release. In a Bayesian analysis, we find that the maximum fractional contribution of EDE to the total energy density is $f_{\\rm EDE} < 0.061$ (without SH0ES) over the redshift range $z\\in[10^3,10^4]$ and that the Hubble constant is constrained to lie within the range $ 66.9 < H_0 < 69.5$ km/s/Mpc (both at 95 \\% C.L.). The data therefore favour a model close to $\\Lambda$CDM, leaving a residual tension of $3.7\\sigma$ with the SH$0$ES Cepheid-based measurement of $H_0$. A comparison with the likelihood profile shows that our conclusions are robust to prior-volume effects. Our new CMB likelihood provides no evidence in favour of a significant EDE component.","url_abs":"https://arxiv.org/abs/2311.00524v1","url_pdf":"https://arxiv.org/pdf/2311.00524v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"improved-planck-constraints-on-axion-like","repo_url":"https://github.com/brinckmann/montepython_public","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}