{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2016:PTA6EBV6KSYAPYVKUNM2J4JV6Q","short_pith_number":"pith:PTA6EBV6","canonical_record":{"source":{"id":"1608.03593","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2016-08-11T20:00:05Z","cross_cats_sorted":["astro-ph.GA","gr-qc"],"title_canon_sha256":"645289cd3ba09d4d5c4c44cc7506b03da65b9a66f88515569a697b5db4d811fa","abstract_canon_sha256":"e51a530912ece6d0ce54e38b860404fc409b1764c617156d638e78ac462b6f2e"},"schema_version":"1.0"},"canonical_sha256":"7cc1e206be54b007e2aaa359a4f135f424471bcda7230c4902db7363e64b7081","source":{"kind":"arxiv","id":"1608.03593","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1608.03593","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"arxiv_version","alias_value":"1608.03593v2","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1608.03593","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"pith_short_12","alias_value":"PTA6EBV6KSYA","created_at":"2026-05-18T12:30:39Z"},{"alias_kind":"pith_short_16","alias_value":"PTA6EBV6KSYAPYVK","created_at":"2026-05-18T12:30:39Z"},{"alias_kind":"pith_short_8","alias_value":"PTA6EBV6","created_at":"2026-05-18T12:30:39Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2016:PTA6EBV6KSYAPYVKUNM2J4JV6Q","target":"record","payload":{"canonical_record":{"source":{"id":"1608.03593","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2016-08-11T20:00:05Z","cross_cats_sorted":["astro-ph.GA","gr-qc"],"title_canon_sha256":"645289cd3ba09d4d5c4c44cc7506b03da65b9a66f88515569a697b5db4d811fa","abstract_canon_sha256":"e51a530912ece6d0ce54e38b860404fc409b1764c617156d638e78ac462b6f2e"},"schema_version":"1.0"},"canonical_sha256":"7cc1e206be54b007e2aaa359a4f135f424471bcda7230c4902db7363e64b7081","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:06:28.342904Z","signature_b64":"+OqZTVPyaMBzh1YPjahgFvJ9c4GZuxOgO3l2Oc89AS/xLfMulQlcP2JNcggTDs2j1QRlDAsba8w96x9mMHxTBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7cc1e206be54b007e2aaa359a4f135f424471bcda7230c4902db7363e64b7081","last_reissued_at":"2026-05-18T01:06:28.342287Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:06:28.342287Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1608.03593","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:06:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WCcuUn7RByVLlIrqUgbr67fLN8T48SYrNqI3c1tk568UAtpj9HIBWu7Uz3j/dX68Z6nV9R2tAHm2xexHWBN2AA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T20:03:10.536631Z"},"content_sha256":"6b166ecf8cd0b69028ec73c492585f437a05ea1d5afd38d496bc4493bfa817ed","schema_version":"1.0","event_id":"sha256:6b166ecf8cd0b69028ec73c492585f437a05ea1d5afd38d496bc4493bfa817ed"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2016:PTA6EBV6KSYAPYVKUNM2J4JV6Q","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Testing General Relativity with Accretion-Flow Imaging of Sgr A*","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA","gr-qc"],"primary_cat":"astro-ph.HE","authors_text":"Abraham Loeb, Avery E. Broderick, Carlos Wang, Dimitrios Psaltis, Sheperd S. Doeleman, Tim Johannsen, Vincent L. Fish","submitted_at":"2016-08-11T20:00:05Z","abstract_excerpt":"The Event Horizon Telescope is a global very-long baseline interferometer capable of probing potential deviations from the Kerr metric, which is believed to provide the unique description of astrophysical black holes. Here we report an updated constraint on the quadrupolar deviation of Sagittarius A* within the context of a radiatively inefficient accretion flow model in a quasi-Kerr background. We also simulate near-future constraints obtainable by the forthcoming eight-station array and show that in this model already a one-day observation can measure the spin magnitude to within $0.005$, th"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1608.03593","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:06:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Or15VL/zD+NFIPzhP+IAYkY/m5+hphoC822GkqI7hsmvFLb+r+eXNDpW7/3bt2LfoCqAFSpa1GwwGFiaV7bDBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T20:03:10.537335Z"},"content_sha256":"011883773a3249f65631a4b50b9300ec0a88b9b8f1da570b24ba8550a9a0b846","schema_version":"1.0","event_id":"sha256:011883773a3249f65631a4b50b9300ec0a88b9b8f1da570b24ba8550a9a0b846"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/bundle.json","state_url":"https://pith.science/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/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":"2026-05-30T20:03:10Z","links":{"resolver":"https://pith.science/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q","bundle":"https://pith.science/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/bundle.json","state":"https://pith.science/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/state.json","well_known_bundle":"https://pith.science/.well-known/pith/PTA6EBV6KSYAPYVKUNM2J4JV6Q/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2016:PTA6EBV6KSYAPYVKUNM2J4JV6Q","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":"e51a530912ece6d0ce54e38b860404fc409b1764c617156d638e78ac462b6f2e","cross_cats_sorted":["astro-ph.GA","gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2016-08-11T20:00:05Z","title_canon_sha256":"645289cd3ba09d4d5c4c44cc7506b03da65b9a66f88515569a697b5db4d811fa"},"schema_version":"1.0","source":{"id":"1608.03593","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1608.03593","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"arxiv_version","alias_value":"1608.03593v2","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1608.03593","created_at":"2026-05-18T01:06:28Z"},{"alias_kind":"pith_short_12","alias_value":"PTA6EBV6KSYA","created_at":"2026-05-18T12:30:39Z"},{"alias_kind":"pith_short_16","alias_value":"PTA6EBV6KSYAPYVK","created_at":"2026-05-18T12:30:39Z"},{"alias_kind":"pith_short_8","alias_value":"PTA6EBV6","created_at":"2026-05-18T12:30:39Z"}],"graph_snapshots":[{"event_id":"sha256:011883773a3249f65631a4b50b9300ec0a88b9b8f1da570b24ba8550a9a0b846","target":"graph","created_at":"2026-05-18T01:06:28Z","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":"The Event Horizon Telescope is a global very-long baseline interferometer capable of probing potential deviations from the Kerr metric, which is believed to provide the unique description of astrophysical black holes. Here we report an updated constraint on the quadrupolar deviation of Sagittarius A* within the context of a radiatively inefficient accretion flow model in a quasi-Kerr background. We also simulate near-future constraints obtainable by the forthcoming eight-station array and show that in this model already a one-day observation can measure the spin magnitude to within $0.005$, th","authors_text":"Abraham Loeb, Avery E. Broderick, Carlos Wang, Dimitrios Psaltis, Sheperd S. Doeleman, Tim Johannsen, Vincent L. Fish","cross_cats":["astro-ph.GA","gr-qc"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2016-08-11T20:00:05Z","title":"Testing General Relativity with Accretion-Flow Imaging of Sgr A*"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1608.03593","kind":"arxiv","version":2},"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":"sha256:6b166ecf8cd0b69028ec73c492585f437a05ea1d5afd38d496bc4493bfa817ed","target":"record","created_at":"2026-05-18T01:06:28Z","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":"e51a530912ece6d0ce54e38b860404fc409b1764c617156d638e78ac462b6f2e","cross_cats_sorted":["astro-ph.GA","gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2016-08-11T20:00:05Z","title_canon_sha256":"645289cd3ba09d4d5c4c44cc7506b03da65b9a66f88515569a697b5db4d811fa"},"schema_version":"1.0","source":{"id":"1608.03593","kind":"arxiv","version":2}},"canonical_sha256":"7cc1e206be54b007e2aaa359a4f135f424471bcda7230c4902db7363e64b7081","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7cc1e206be54b007e2aaa359a4f135f424471bcda7230c4902db7363e64b7081","first_computed_at":"2026-05-18T01:06:28.342287Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:06:28.342287Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"+OqZTVPyaMBzh1YPjahgFvJ9c4GZuxOgO3l2Oc89AS/xLfMulQlcP2JNcggTDs2j1QRlDAsba8w96x9mMHxTBw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:06:28.342904Z","signed_message":"canonical_sha256_bytes"},"source_id":"1608.03593","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:6b166ecf8cd0b69028ec73c492585f437a05ea1d5afd38d496bc4493bfa817ed","sha256:011883773a3249f65631a4b50b9300ec0a88b9b8f1da570b24ba8550a9a0b846"],"state_sha256":"f28ca00b1e03c0ca06dd77b98a4714fcdbe4d257cbfdec9e3033325f70425967"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"uJMK32gzcFZjrBDd3gybPXAeCkTX/KDboTit6F8nbwmWHQDIgxy949FnGTe3it/9SMzrS03KYIvYSsLYUdgZDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-30T20:03:10.540899Z","bundle_sha256":"ae74a8b274f13adf9766961c1c1345f13b4d02b22de0852d9537e9046b0591a9"}}