{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2010:A27BL3URTP3GBCYM26VQCQICU5","short_pith_number":"pith:A27BL3UR","schema_version":"1.0","canonical_sha256":"06be15ee919bf6608b0cd7ab014102a76540fd8429f9665aa09d11656ee574d0","source":{"kind":"arxiv","id":"1001.4078","version":1},"attestation_state":"computed","paper":{"title":"Keck telescope constraint on cosmological variation of the proton-to-electron mass ratio","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"(2) VU Univ., (3) Univ. Victoria, (4) UCO/Lick Obs. Univ. Calfornia Santa Cruz, 5), (5) Univ. Amsterdam, (6) Yale Univ., (7) IoA, Adrian L. Malec (1), Australia, Canada, Jason Tumlinson (6), J. Xavier Prochaska (4), Lex Kaper (2, Michael T. Murphy (1), Nikola Milutinovic (3), Robert F. Carswell (7), Ruth Buning (2), S. L. Ellison (3), The Netherlands, UK), Univ. Cambridge, USA, Wim Ubachs (2) ((1) Swinburne Univ.","submitted_at":"2010-01-22T21:10:36Z","abstract_excerpt":"Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck telescope, the optical echelle spectrum has the highest resolving power and largest number (86) of H_2 transitions in such analyses so far. Also, (seven) HD transitions are used for the first time to constrain mu-variation. These factors, and an analysis employing the fewest possible free parameters, strongly constrain mu's relative deviation from the current laborat"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1001.4078","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T21:10:36Z","cross_cats_sorted":[],"title_canon_sha256":"57f5da5e1df591856ee71eda5f10172c2668e40497eca447dd7bcdd7320e4b69","abstract_canon_sha256":"142019e1d71c986159f98198d97a4c9663abfd5c882ca846c70675a26d758288"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:09:30.937232Z","signature_b64":"JOxLeO2jU0rGgboI/5WkyhNPUqvD3ezNcPmJPvYPBCBNq6hBbsLAvybB+hFuWRN+tuA6mFes7ZFMOOj1oMfJBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"06be15ee919bf6608b0cd7ab014102a76540fd8429f9665aa09d11656ee574d0","last_reissued_at":"2026-05-18T02:09:30.936590Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:09:30.936590Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Keck telescope constraint on cosmological variation of the proton-to-electron mass ratio","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"(2) VU Univ., (3) Univ. Victoria, (4) UCO/Lick Obs. Univ. Calfornia Santa Cruz, 5), (5) Univ. Amsterdam, (6) Yale Univ., (7) IoA, Adrian L. Malec (1), Australia, Canada, Jason Tumlinson (6), J. Xavier Prochaska (4), Lex Kaper (2, Michael T. Murphy (1), Nikola Milutinovic (3), Robert F. Carswell (7), Ruth Buning (2), S. L. Ellison (3), The Netherlands, UK), Univ. Cambridge, USA, Wim Ubachs (2) ((1) Swinburne Univ.","submitted_at":"2010-01-22T21:10:36Z","abstract_excerpt":"Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck telescope, the optical echelle spectrum has the highest resolving power and largest number (86) of H_2 transitions in such analyses so far. Also, (seven) HD transitions are used for the first time to constrain mu-variation. These factors, and an analysis employing the fewest possible free parameters, strongly constrain mu's relative deviation from the current laborat"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1001.4078","kind":"arxiv","version":1},"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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1001.4078","created_at":"2026-05-18T02:09:30.936681+00:00"},{"alias_kind":"arxiv_version","alias_value":"1001.4078v1","created_at":"2026-05-18T02:09:30.936681+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1001.4078","created_at":"2026-05-18T02:09:30.936681+00:00"},{"alias_kind":"pith_short_12","alias_value":"A27BL3URTP3G","created_at":"2026-05-18T12:26:05.355336+00:00"},{"alias_kind":"pith_short_16","alias_value":"A27BL3URTP3GBCYM","created_at":"2026-05-18T12:26:05.355336+00:00"},{"alias_kind":"pith_short_8","alias_value":"A27BL3UR","created_at":"2026-05-18T12:26:05.355336+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5","json":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5.json","graph_json":"https://pith.science/api/pith-number/A27BL3URTP3GBCYM26VQCQICU5/graph.json","events_json":"https://pith.science/api/pith-number/A27BL3URTP3GBCYM26VQCQICU5/events.json","paper":"https://pith.science/paper/A27BL3UR"},"agent_actions":{"view_html":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5","download_json":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5.json","view_paper":"https://pith.science/paper/A27BL3UR","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1001.4078&json=true","fetch_graph":"https://pith.science/api/pith-number/A27BL3URTP3GBCYM26VQCQICU5/graph.json","fetch_events":"https://pith.science/api/pith-number/A27BL3URTP3GBCYM26VQCQICU5/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5/action/timestamp_anchor","attest_storage":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5/action/storage_attestation","attest_author":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5/action/author_attestation","sign_citation":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5/action/citation_signature","submit_replication":"https://pith.science/pith/A27BL3URTP3GBCYM26VQCQICU5/action/replication_record"}},"created_at":"2026-05-18T02:09:30.936681+00:00","updated_at":"2026-05-18T02:09:30.936681+00:00"}