{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:4MBW6NMTDR643ZXAHM3TEUH7NU","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":"73b99bb38bb977f128d86fbf8336c5c9111dd69ec95819a4719faa4c47dc9af6","cross_cats_sorted":["physics.pop-ph"],"license":"http://creativecommons.org/licenses/publicdomain/","primary_cat":"gr-qc","submitted_at":"2015-03-13T23:17:10Z","title_canon_sha256":"59771f271fa841de40a0e53dfe339ce0f3abe98f84a00c50fdfb25ef08b9211e"},"schema_version":"1.0","source":{"id":"1503.05845","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1503.05845","created_at":"2026-05-18T02:18:31Z"},{"alias_kind":"arxiv_version","alias_value":"1503.05845v3","created_at":"2026-05-18T02:18:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1503.05845","created_at":"2026-05-18T02:18:31Z"},{"alias_kind":"pith_short_12","alias_value":"4MBW6NMTDR64","created_at":"2026-05-18T12:29:05Z"},{"alias_kind":"pith_short_16","alias_value":"4MBW6NMTDR643ZXA","created_at":"2026-05-18T12:29:05Z"},{"alias_kind":"pith_short_8","alias_value":"4MBW6NMT","created_at":"2026-05-18T12:29:05Z"}],"graph_snapshots":[{"event_id":"sha256:ecabc8c5e92479b0abd57f85593dd1fa2baf89fea223fe629c8a4d222a54525e","target":"graph","created_at":"2026-05-18T02:18:31Z","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":"While special relativity imposes an absolute speed limit at the speed of light, our Universe is not empty Minkowski spacetime. The constituents that fill the interstellar/intergalactic vacuum, including the cosmic microwave background photons, impose a lower speed limit on any object travelling at relativistic velocities. Scattering of cosmic microwave phtotons from an ultra-relativistic object may create radiation with a characteristic signature allowing the detection of such objects at large distances.","authors_text":"Steven Wilkinson, Ulvi Yurtsever","cross_cats":["physics.pop-ph"],"headline":"","license":"http://creativecommons.org/licenses/publicdomain/","primary_cat":"gr-qc","submitted_at":"2015-03-13T23:17:10Z","title":"Limits and Signatures of Relativistic Spaceflight"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1503.05845","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":"sha256:264562b4218f1dfeef97d8a610d5b3eb08541846162bf38479e99408b254bc9c","target":"record","created_at":"2026-05-18T02:18:31Z","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":"73b99bb38bb977f128d86fbf8336c5c9111dd69ec95819a4719faa4c47dc9af6","cross_cats_sorted":["physics.pop-ph"],"license":"http://creativecommons.org/licenses/publicdomain/","primary_cat":"gr-qc","submitted_at":"2015-03-13T23:17:10Z","title_canon_sha256":"59771f271fa841de40a0e53dfe339ce0f3abe98f84a00c50fdfb25ef08b9211e"},"schema_version":"1.0","source":{"id":"1503.05845","kind":"arxiv","version":3}},"canonical_sha256":"e3036f35931c7dcde6e03b373250ff6d03469f4721b3a6dbabc5171a0695b2bf","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e3036f35931c7dcde6e03b373250ff6d03469f4721b3a6dbabc5171a0695b2bf","first_computed_at":"2026-05-18T02:18:31.053837Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:18:31.053837Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7/K3PaJUtlgVTPNack8fkqjwitwTt3xsJVSO3M7ZHoP3lh8m6YHM6/WudJPxqywZ27d+MueRge+3Ksh29PnQAQ==","signature_status":"signed_v1","signed_at":"2026-05-18T02:18:31.054265Z","signed_message":"canonical_sha256_bytes"},"source_id":"1503.05845","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:264562b4218f1dfeef97d8a610d5b3eb08541846162bf38479e99408b254bc9c","sha256:ecabc8c5e92479b0abd57f85593dd1fa2baf89fea223fe629c8a4d222a54525e"],"state_sha256":"8f62e71b167324d44e77af5eefcc0936c573396a28ffe04b8a0e118d0b29b71d"}