{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2010:Q7JTRV2VPOHDKFQRPTQ6LMMD6H","short_pith_number":"pith:Q7JTRV2V","canonical_record":{"source":{"id":"1001.3975","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T12:30:51Z","cross_cats_sorted":["astro-ph.IM"],"title_canon_sha256":"1cb794707c961f804ab33a0e13c00a8e9176342da257472365bfd8bfb42f8aba","abstract_canon_sha256":"0248a7b3a763d1fd403746daae22e8035746b85ac19d154ff8f02202e3c068fd"},"schema_version":"1.0"},"canonical_sha256":"87d338d7557b8e3516117ce1e5b183f1fbfb883f8899e9170cedf0d7665934cc","source":{"kind":"arxiv","id":"1001.3975","version":3},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1001.3975","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"arxiv_version","alias_value":"1001.3975v3","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1001.3975","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"pith_short_12","alias_value":"Q7JTRV2VPOHD","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_16","alias_value":"Q7JTRV2VPOHDKFQR","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_8","alias_value":"Q7JTRV2V","created_at":"2026-05-18T12:26:12Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2010:Q7JTRV2VPOHDKFQRPTQ6LMMD6H","target":"record","payload":{"canonical_record":{"source":{"id":"1001.3975","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T12:30:51Z","cross_cats_sorted":["astro-ph.IM"],"title_canon_sha256":"1cb794707c961f804ab33a0e13c00a8e9176342da257472365bfd8bfb42f8aba","abstract_canon_sha256":"0248a7b3a763d1fd403746daae22e8035746b85ac19d154ff8f02202e3c068fd"},"schema_version":"1.0"},"canonical_sha256":"87d338d7557b8e3516117ce1e5b183f1fbfb883f8899e9170cedf0d7665934cc","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:56:22.915384Z","signature_b64":"OdlOHzsrfq5Q5aRbhn0P7RIvAFhtxU1E+oK1hdtWweGwWUiWdfmrMQSVTCrNX8vkxmKitTla9dumwgsg5b3BDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"87d338d7557b8e3516117ce1e5b183f1fbfb883f8899e9170cedf0d7665934cc","last_reissued_at":"2026-05-18T03:56:22.914811Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:56:22.914811Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1001.3975","source_version":3,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:56:22Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NxtAc5M8RQSKQ56FvbqBrE8F1Jts8OuprV+w9linp4ymOv78Y6fzcQRDIudXwfLU1QwfO6Eqvc4Q6PqG1SAuCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T03:03:45.316823Z"},"content_sha256":"e95be332a48812f3f04324ad27b965524773a424868047338c0d1e095e94f107","schema_version":"1.0","event_id":"sha256:e95be332a48812f3f04324ad27b965524773a424868047338c0d1e095e94f107"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2010:Q7JTRV2VPOHDKFQRPTQ6LMMD6H","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Possible direct measurement of the expansion rate of the universe","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.IM"],"primary_cat":"astro-ph.CO","authors_text":"Shi Qi, Tan Lu","submitted_at":"2010-01-22T12:30:51Z","abstract_excerpt":"A new method is proposed for directly measuring the expansion rate of the universe through very precise measurement of the fluence of extremely stable sources. The method is based on the definition of the luminosity distance and its change along the time due to the cosmic expansion. It is argued that galaxies may be chosen as the targets of the observation to perform the measurement. We show that, by simultaneously increasing the observation time and physically adding the fluences from different galaxies, the requirement on the relative precision of the detector for an observation of 1 second "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1001.3975","kind":"arxiv","version":3},"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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:56:22Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"fYiD7m9JQbBzBRGyV6Z0Emv9Nk9R7V/T7OrSp6CF1hKfayuS5jeT2qLl1IS0KX3HVIbPQoTQdSwxpTO18sUFCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T03:03:45.317251Z"},"content_sha256":"e987b3969f11c9ecbde63ae055f03f9c5d961da76e307a373da18847427f3a7a","schema_version":"1.0","event_id":"sha256:e987b3969f11c9ecbde63ae055f03f9c5d961da76e307a373da18847427f3a7a"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/bundle.json","state_url":"https://pith.science/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-27T03:03:45Z","links":{"resolver":"https://pith.science/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H","bundle":"https://pith.science/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/bundle.json","state":"https://pith.science/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/state.json","well_known_bundle":"https://pith.science/.well-known/pith/Q7JTRV2VPOHDKFQRPTQ6LMMD6H/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2010:Q7JTRV2VPOHDKFQRPTQ6LMMD6H","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"0248a7b3a763d1fd403746daae22e8035746b85ac19d154ff8f02202e3c068fd","cross_cats_sorted":["astro-ph.IM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T12:30:51Z","title_canon_sha256":"1cb794707c961f804ab33a0e13c00a8e9176342da257472365bfd8bfb42f8aba"},"schema_version":"1.0","source":{"id":"1001.3975","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1001.3975","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"arxiv_version","alias_value":"1001.3975v3","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1001.3975","created_at":"2026-05-18T03:56:22Z"},{"alias_kind":"pith_short_12","alias_value":"Q7JTRV2VPOHD","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_16","alias_value":"Q7JTRV2VPOHDKFQR","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_8","alias_value":"Q7JTRV2V","created_at":"2026-05-18T12:26:12Z"}],"graph_snapshots":[{"event_id":"sha256:e987b3969f11c9ecbde63ae055f03f9c5d961da76e307a373da18847427f3a7a","target":"graph","created_at":"2026-05-18T03:56:22Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"A new method is proposed for directly measuring the expansion rate of the universe through very precise measurement of the fluence of extremely stable sources. The method is based on the definition of the luminosity distance and its change along the time due to the cosmic expansion. It is argued that galaxies may be chosen as the targets of the observation to perform the measurement. We show that, by simultaneously increasing the observation time and physically adding the fluences from different galaxies, the requirement on the relative precision of the detector for an observation of 1 second ","authors_text":"Shi Qi, Tan Lu","cross_cats":["astro-ph.IM"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T12:30:51Z","title":"Possible direct measurement of the expansion rate of the universe"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1001.3975","kind":"arxiv","version":3},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:e95be332a48812f3f04324ad27b965524773a424868047338c0d1e095e94f107","target":"record","created_at":"2026-05-18T03:56:22Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"0248a7b3a763d1fd403746daae22e8035746b85ac19d154ff8f02202e3c068fd","cross_cats_sorted":["astro-ph.IM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-01-22T12:30:51Z","title_canon_sha256":"1cb794707c961f804ab33a0e13c00a8e9176342da257472365bfd8bfb42f8aba"},"schema_version":"1.0","source":{"id":"1001.3975","kind":"arxiv","version":3}},"canonical_sha256":"87d338d7557b8e3516117ce1e5b183f1fbfb883f8899e9170cedf0d7665934cc","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"87d338d7557b8e3516117ce1e5b183f1fbfb883f8899e9170cedf0d7665934cc","first_computed_at":"2026-05-18T03:56:22.914811Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:56:22.914811Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OdlOHzsrfq5Q5aRbhn0P7RIvAFhtxU1E+oK1hdtWweGwWUiWdfmrMQSVTCrNX8vkxmKitTla9dumwgsg5b3BDA==","signature_status":"signed_v1","signed_at":"2026-05-18T03:56:22.915384Z","signed_message":"canonical_sha256_bytes"},"source_id":"1001.3975","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e95be332a48812f3f04324ad27b965524773a424868047338c0d1e095e94f107","sha256:e987b3969f11c9ecbde63ae055f03f9c5d961da76e307a373da18847427f3a7a"],"state_sha256":"4ad270a50bba4b5efaab7f292148181077ced3c0a76361990537177abfb6aecd"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"pvq/YI7tQ80Y6vj6PPo0IRRqMyFyVVRogcTVExv3n+IvRzSlFuDR9gWyVF+ebBKfGV+y1EulOqZ0/zYKfBkXCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-27T03:03:45.320044Z","bundle_sha256":"403c5529c6e796347d767150b7cd1ea2a7a6f8f748b1531147d3f9e663f24248"}}