{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:1997:IFEVCSJC5C45JSOMN2J3ML5IDY","short_pith_number":"pith:IFEVCSJC","schema_version":"1.0","canonical_sha256":"4149514922e8b9d4c9cc6e93b62fa81e3e5715fe51b604e75ebffbf3f282ce61","source":{"kind":"arxiv","id":"astro-ph/9704285","version":2},"attestation_state":"computed","paper":{"title":"Comment on the Measurement of Cosmological Birefringence","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"J. P. Leahy (University of Manchester)","submitted_at":"1997-04-29T19:14:34Z","abstract_excerpt":"Nodland and Ralston (astro-ph/9704196) claim evidence for a wavelength-independent cosmic birefringence. Although it has been shown (astro-ph/9704247, astro-ph/9704263) that the data analysed did not support this conclusion, the possibility of such an effect remains interesting. Here I present a much more accurate test using high-resolution radio images of distant radio galaxies and quasars. A preliminary application sets an upper limit about thirty times lower than the original claim."},"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":"astro-ph/9704285","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1997-04-29T19:14:34Z","cross_cats_sorted":[],"title_canon_sha256":"80be4da280f8d052d5589721aedbdf8d97042b8a9688e239b8048152b34394da","abstract_canon_sha256":"d79c8cb2df134f7f918b071ae68566e4b71346644650000f9d70cd88e567d1f1"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T15:07:39.163955Z","signature_b64":"HvzRgENoto/4IH7Bl13GzxNsv1M9q8FfMB3Ev7ngW9MfepvkJPJpFy198ZGOon2Ab9hwuJWzgLjpWnioxearAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"4149514922e8b9d4c9cc6e93b62fa81e3e5715fe51b604e75ebffbf3f282ce61","last_reissued_at":"2026-07-04T15:07:39.163476Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T15:07:39.163476Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Comment on the Measurement of Cosmological Birefringence","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"J. P. Leahy (University of Manchester)","submitted_at":"1997-04-29T19:14:34Z","abstract_excerpt":"Nodland and Ralston (astro-ph/9704196) claim evidence for a wavelength-independent cosmic birefringence. Although it has been shown (astro-ph/9704247, astro-ph/9704263) that the data analysed did not support this conclusion, the possibility of such an effect remains interesting. Here I present a much more accurate test using high-resolution radio images of distant radio galaxies and quasars. A preliminary application sets an upper limit about thirty times lower than the original claim."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9704285","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/astro-ph/9704285/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"astro-ph/9704285","created_at":"2026-07-04T15:07:39.163533+00:00"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9704285v2","created_at":"2026-07-04T15:07:39.163533+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9704285","created_at":"2026-07-04T15:07:39.163533+00:00"},{"alias_kind":"pith_short_12","alias_value":"IFEVCSJC5C45","created_at":"2026-07-04T15:07:39.163533+00:00"},{"alias_kind":"pith_short_16","alias_value":"IFEVCSJC5C45JSOM","created_at":"2026-07-04T15:07:39.163533+00:00"},{"alias_kind":"pith_short_8","alias_value":"IFEVCSJC","created_at":"2026-07-04T15:07:39.163533+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/IFEVCSJC5C45JSOMN2J3ML5IDY","json":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY.json","graph_json":"https://pith.science/api/pith-number/IFEVCSJC5C45JSOMN2J3ML5IDY/graph.json","events_json":"https://pith.science/api/pith-number/IFEVCSJC5C45JSOMN2J3ML5IDY/events.json","paper":"https://pith.science/paper/IFEVCSJC"},"agent_actions":{"view_html":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY","download_json":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY.json","view_paper":"https://pith.science/paper/IFEVCSJC","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=astro-ph/9704285&json=true","fetch_graph":"https://pith.science/api/pith-number/IFEVCSJC5C45JSOMN2J3ML5IDY/graph.json","fetch_events":"https://pith.science/api/pith-number/IFEVCSJC5C45JSOMN2J3ML5IDY/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY/action/timestamp_anchor","attest_storage":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY/action/storage_attestation","attest_author":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY/action/author_attestation","sign_citation":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY/action/citation_signature","submit_replication":"https://pith.science/pith/IFEVCSJC5C45JSOMN2J3ML5IDY/action/replication_record"}},"created_at":"2026-07-04T15:07:39.163533+00:00","updated_at":"2026-07-04T15:07:39.163533+00:00"}