{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"d1d79142e1129da3d17c593f9ca8f75c999ad8d2ea04ce32eb286b084c573f99","created":"2026-10-03T07:18:02Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011","ed264645728bed1ec687ad4bd3875390250b8f5cab07bf83f47c6553d9b6de0f"],"salt":"ee2da7ac7e9cabbad9f4589e7f0df36b2717f4da705dfc9b566d55ed230326b5","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cosmo.hubble-tension.oldest-stars-age","kind":"well-posed","literature_status":"open","n":"1","parents":[{"note":"","parent_revision":"ed264645728bed1ec687ad4bd3875390250b8f5cab07bf83f47c6553d9b6de0f","relation":"special_case"}],"plain":"The universe cannot be younger than its oldest stars. A faster expansion rate implies a younger universe, so precise ages of the oldest stars test which Hubble constant is right.","posed_since":"","precise":"In flat LCDM the age is $t0 = 13.8\\,\\mathrm{Gyr}$ for $h = 0.674, \\Omega_m = 0.315$ and about $12.9\\,\\mathrm{Gyr}$ for $h = 0.73, \\Omega_m = 0.3$, while the oldest globular clusters, metal-poor stars and white dwarfs give ages near $13.3\\text{ to }13.6\\,\\mathrm{Gyr}$ plus a formation delay of order $0.2\\,\\mathrm{Gyr}$. Determine whether these ages exceed the age allowed for $h = 0.73$ at more than $3\\sigma$, with distance, reddening, alpha-element and stellar-physics systematics below $0.3\\,\\mathrm{Gyr}$. Cimatti and Moresco (2023, arXiv:2302.07899) obtained $h < 0.706$ from the most accurate ages.","problem_ref":null,"references":"","settled_by":"Globular-cluster ages from Gaia distances and JWST photometry with full stellar-model error budgets, cross-checked with white-dwarf cooling ages.","status_note":"","title":"Are the oldest stars too old for a Hubble constant of 0.73?","topic_ref":"7274d4f6495a643569c4fecb6957a3a928df8172b93a2b26d1dc5043075bd891"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"09249554d454444bf0dc4263eb84b6cc32d209a93365019d9c23f02d8cefbc73","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"c6cd24bdd0394f7e0da6cb95a1b0a8ddce86c70425fed89fb4171b0b2cf152da","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"OoZWiNFyY5hSpsj5Pl5xueRrIU0426_tE-A4RaAB0_9G66bJLBhp2HsxvR9Gl4NhdXg3cddpOGRxth6j28azDg"},"schema":"pubphys.envelope/1"},"record_hash":"09249554d454444bf0dc4263eb84b6cc32d209a93365019d9c23f02d8cefbc73","leaf_index":1260}