{"paper":{"title":"Astrophysical Limits on the Evolution of Dimensionless Physical Constants over Cosmological Time","license":"","headline":"","cross_cats":["hep-ex","hep-ph"],"primary_cat":"astro-ph","authors_text":"Antoinette Songaila (Univ. of Hawaii, IfA), Lennox L. Cowie","submitted_at":"1995-07-16T00:49:50Z","abstract_excerpt":"We report new upper limits on any possible long-term time variation of the ratio of the electron to proton masses, $(m_e/m_p)$, the fine-structure constant, ($\\alpha$), and the quantity $\\alpha^2 g_p(m_e/m_p)$, where $g_p$ is the proton gyromagnetic ratio. These limits are based on extremely high precision observations of H$_2$, Si$^{3+}$, C$^0$ and H$^0$ in high-redshift quasar absorption lines. They amount to 95\\% confidence ranges of $(-7.6\\to 9.7) \\times 10^{-14}$ yr$^{-1}$ for ($m_e/m_p$), $(-4.6\\to 4.2)\\times 10^{-14}$ yr$^{-1}$ for $\\alpha$\\ and $(-2.2\\to 4.2) \\times 10^{-15}$ yr$^{-1}$"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9507062","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}