{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:D44FL73YMYTXUE7T6CJW4Z7Q37","short_pith_number":"pith:D44FL73Y","canonical_record":{"source":{"id":"1304.5691","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2013-04-21T05:28:12Z","cross_cats_sorted":["astro-ph.HE"],"title_canon_sha256":"1a8ab44b798916f73dfbe9dc7943ff6a421880e0b40e2cc95614026920aa93d3","abstract_canon_sha256":"f7684b17bbcf02a8384daf1236945189c980c0e6e7cf17b2dfd3a1401b504f28"},"schema_version":"1.0"},"canonical_sha256":"1f3855ff7866277a13f3f0936e67f0dffa82b2cec47feaeece039de385bc6ac0","source":{"kind":"arxiv","id":"1304.5691","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1304.5691","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"arxiv_version","alias_value":"1304.5691v2","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1304.5691","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"pith_short_12","alias_value":"D44FL73YMYTX","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_16","alias_value":"D44FL73YMYTXUE7T","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_8","alias_value":"D44FL73Y","created_at":"2026-05-18T12:27:40Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:D44FL73YMYTXUE7T6CJW4Z7Q37","target":"record","payload":{"canonical_record":{"source":{"id":"1304.5691","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2013-04-21T05:28:12Z","cross_cats_sorted":["astro-ph.HE"],"title_canon_sha256":"1a8ab44b798916f73dfbe9dc7943ff6a421880e0b40e2cc95614026920aa93d3","abstract_canon_sha256":"f7684b17bbcf02a8384daf1236945189c980c0e6e7cf17b2dfd3a1401b504f28"},"schema_version":"1.0"},"canonical_sha256":"1f3855ff7866277a13f3f0936e67f0dffa82b2cec47feaeece039de385bc6ac0","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:26:33.339656Z","signature_b64":"vFiEY5kH9acZWBjbhWx3EGdC3Ec8XHs8GyN2x1NJSYFFlSg1G3CifFmNKJ3EuGw3dCztGkUkzJVt41ymG7oCBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1f3855ff7866277a13f3f0936e67f0dffa82b2cec47feaeece039de385bc6ac0","last_reissued_at":"2026-05-18T03:26:33.339221Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:26:33.339221Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1304.5691","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":"2026-05-18T03:26:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1FJKkbRcnLngJrkb9dCXjiH5Whh/f8dZMPR//8jRz4mhozhpvxtchRU9F2SAIbZRdzTDjUX78A04735loKR1BQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T21:06:23.690273Z"},"content_sha256":"bb16301006d7704814b803780504e4ea3c08d799f9e858ecfc1b312551b74bb6","schema_version":"1.0","event_id":"sha256:bb16301006d7704814b803780504e4ea3c08d799f9e858ecfc1b312551b74bb6"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:D44FL73YMYTXUE7T6CJW4Z7Q37","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Can the supermassive objects at the centers of galaxies be traversable wormholes? The first test of strong gravity for mm/sub-mm VLBI facilities","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"gr-qc","authors_text":"Cosimo Bambi","submitted_at":"2013-04-21T05:28:12Z","abstract_excerpt":"The near future mm/sub-mm VLBI experiments are ambitious projects aiming at imaging the \"shadow\" of the supermassive black hole candidate at the center of the Milky Way and of the ones in nearby galaxies. An accurate observation of the shape of the shadow can potentially test the nature of these objects and verify if they are Kerr black holes, as predicted by general relativity. However, previous work on the subject has shown that the shadows produced in other spacetimes are very similar to the one of the Kerr background, suggesting that tests of strong gravity are not really possible with the"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1304.5691","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":"2026-05-18T03:26:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"3oYcrDpbNcoC/QwOyveMnCiOWfcWfa/OOdECR8WLUOKtCUq3NLfWEWHmoFYD98KseTd0uPNh1eSIndEuW7ZoAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T21:06:23.690960Z"},"content_sha256":"6030a3e79da208eb1a27a8ff2b4a8f4ee4efe89f8f1c3ac76a5dd90fa311fe12","schema_version":"1.0","event_id":"sha256:6030a3e79da208eb1a27a8ff2b4a8f4ee4efe89f8f1c3ac76a5dd90fa311fe12"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/bundle.json","state_url":"https://pith.science/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/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":"2026-05-25T21:06:23Z","links":{"resolver":"https://pith.science/pith/D44FL73YMYTXUE7T6CJW4Z7Q37","bundle":"https://pith.science/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/bundle.json","state":"https://pith.science/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/state.json","well_known_bundle":"https://pith.science/.well-known/pith/D44FL73YMYTXUE7T6CJW4Z7Q37/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:D44FL73YMYTXUE7T6CJW4Z7Q37","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":"f7684b17bbcf02a8384daf1236945189c980c0e6e7cf17b2dfd3a1401b504f28","cross_cats_sorted":["astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2013-04-21T05:28:12Z","title_canon_sha256":"1a8ab44b798916f73dfbe9dc7943ff6a421880e0b40e2cc95614026920aa93d3"},"schema_version":"1.0","source":{"id":"1304.5691","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1304.5691","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"arxiv_version","alias_value":"1304.5691v2","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1304.5691","created_at":"2026-05-18T03:26:33Z"},{"alias_kind":"pith_short_12","alias_value":"D44FL73YMYTX","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_16","alias_value":"D44FL73YMYTXUE7T","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_8","alias_value":"D44FL73Y","created_at":"2026-05-18T12:27:40Z"}],"graph_snapshots":[{"event_id":"sha256:6030a3e79da208eb1a27a8ff2b4a8f4ee4efe89f8f1c3ac76a5dd90fa311fe12","target":"graph","created_at":"2026-05-18T03:26:33Z","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 near future mm/sub-mm VLBI experiments are ambitious projects aiming at imaging the \"shadow\" of the supermassive black hole candidate at the center of the Milky Way and of the ones in nearby galaxies. An accurate observation of the shape of the shadow can potentially test the nature of these objects and verify if they are Kerr black holes, as predicted by general relativity. However, previous work on the subject has shown that the shadows produced in other spacetimes are very similar to the one of the Kerr background, suggesting that tests of strong gravity are not really possible with the","authors_text":"Cosimo Bambi","cross_cats":["astro-ph.HE"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2013-04-21T05:28:12Z","title":"Can the supermassive objects at the centers of galaxies be traversable wormholes? The first test of strong gravity for mm/sub-mm VLBI facilities"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1304.5691","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:bb16301006d7704814b803780504e4ea3c08d799f9e858ecfc1b312551b74bb6","target":"record","created_at":"2026-05-18T03:26:33Z","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":"f7684b17bbcf02a8384daf1236945189c980c0e6e7cf17b2dfd3a1401b504f28","cross_cats_sorted":["astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2013-04-21T05:28:12Z","title_canon_sha256":"1a8ab44b798916f73dfbe9dc7943ff6a421880e0b40e2cc95614026920aa93d3"},"schema_version":"1.0","source":{"id":"1304.5691","kind":"arxiv","version":2}},"canonical_sha256":"1f3855ff7866277a13f3f0936e67f0dffa82b2cec47feaeece039de385bc6ac0","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"1f3855ff7866277a13f3f0936e67f0dffa82b2cec47feaeece039de385bc6ac0","first_computed_at":"2026-05-18T03:26:33.339221Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:26:33.339221Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"vFiEY5kH9acZWBjbhWx3EGdC3Ec8XHs8GyN2x1NJSYFFlSg1G3CifFmNKJ3EuGw3dCztGkUkzJVt41ymG7oCBA==","signature_status":"signed_v1","signed_at":"2026-05-18T03:26:33.339656Z","signed_message":"canonical_sha256_bytes"},"source_id":"1304.5691","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:bb16301006d7704814b803780504e4ea3c08d799f9e858ecfc1b312551b74bb6","sha256:6030a3e79da208eb1a27a8ff2b4a8f4ee4efe89f8f1c3ac76a5dd90fa311fe12"],"state_sha256":"6a58c788bf906a1b99e7d4397a1815ea7599374c29081fe1715dc42b09346f9d"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hKSwmCcHdPNwRAUFc3qsCMq2OdOUF69Ul5sAkhZRntG7XbCvTUPrGJ2VxTRZmqs1iK2YLapHCu92DJE/DgG2Bg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T21:06:23.694331Z","bundle_sha256":"fd666867a4282ba4ece28a39d2841bc8253651e0958aecf853b45b8569516366"}}