{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:TBL2YBHHLXXFHUMSL4IPZCDUIE","short_pith_number":"pith:TBL2YBHH","canonical_record":{"source":{"id":"1911.07695","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2019-11-18T15:20:03Z","cross_cats_sorted":["astro-ph.HE"],"title_canon_sha256":"e3fe7dd38164be653065d2c9670aa5b2f1c67cf7203d4d1a8320095dd131c788","abstract_canon_sha256":"b9d7d9a65a54a384d30330a6508ab6f23d893949671c3dff2b289b30724ab797"},"schema_version":"1.0"},"canonical_sha256":"9857ac04e75dee53d1925f10fc8874413de3110e905cecb46a69999db42be244","source":{"kind":"arxiv","id":"1911.07695","version":3},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1911.07695","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"arxiv_version","alias_value":"1911.07695v3","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1911.07695","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_12","alias_value":"TBL2YBHHLXXF","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_16","alias_value":"TBL2YBHHLXXFHUMS","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_8","alias_value":"TBL2YBHH","created_at":"2026-07-05T01:31:09Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:TBL2YBHHLXXFHUMSL4IPZCDUIE","target":"record","payload":{"canonical_record":{"source":{"id":"1911.07695","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2019-11-18T15:20:03Z","cross_cats_sorted":["astro-ph.HE"],"title_canon_sha256":"e3fe7dd38164be653065d2c9670aa5b2f1c67cf7203d4d1a8320095dd131c788","abstract_canon_sha256":"b9d7d9a65a54a384d30330a6508ab6f23d893949671c3dff2b289b30724ab797"},"schema_version":"1.0"},"canonical_sha256":"9857ac04e75dee53d1925f10fc8874413de3110e905cecb46a69999db42be244","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T01:31:09.085887Z","signature_b64":"5eXaG9YhWNc3iX7ilKQp2bBamhjU5qwxhmpIgE9P9ypEtvDa8VWjBtZ8uSAeMa7AGUNgjgkkupfMGevnV22cBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9857ac04e75dee53d1925f10fc8874413de3110e905cecb46a69999db42be244","last_reissued_at":"2026-07-05T01:31:09.085461Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T01:31:09.085461Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1911.07695","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":"2026-07-05T01:31:09Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"YIczWxDGiIlcIp5j2s83iK3/1xkyCafQSSCAHva9vWDwrwhkwQBBVZU1aaIU5x9BbUOQqoll6umlvLnv3ikQDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-17T03:18:50.710206Z"},"content_sha256":"06d0a384f82f1a8ca69f0e0e534b52808bbd5b146f3799aec8f316de2368168f","schema_version":"1.0","event_id":"sha256:06d0a384f82f1a8ca69f0e0e534b52808bbd5b146f3799aec8f316de2368168f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:TBL2YBHHLXXFHUMSL4IPZCDUIE","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Silhouettes of invisible black holes","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"gr-qc","authors_text":"Natalia O. Nazarova, Vyacheslav I. Dokuchaev","submitted_at":"2019-11-18T15:20:03Z","abstract_excerpt":"In general relativity, isolated black holes are invisible due to an infinitely large redshift of photons propagating from the event horizon to the remote observer. However, the dark shadow (silhouette) of a black hole can be visible on the background of matter radiation lensed by the gravitational field of black holes. The black hole shadow is the celestial sphere projection of the cross section of photon capture by the black hole. If the illuminating background is far behind the black hole (at a distance much greater than the event horizon radius), a classic black hole shadow of a maximal siz"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1911.07695","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1911.07695/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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T01:31:09Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"APTPiMxk9V24Bl1Us7AypHZh416smIZOx5wZmpIO+xRSkwI50B5Ah5FP2xSOAh5tawUTmKkhkq2IsnjT+lP6Dw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-17T03:18:50.710598Z"},"content_sha256":"b6bdcccda8101abf87bd6c54a83bcf0970313f23faa7d9e8c97df22ea6580e5d","schema_version":"1.0","event_id":"sha256:b6bdcccda8101abf87bd6c54a83bcf0970313f23faa7d9e8c97df22ea6580e5d"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/bundle.json","state_url":"https://pith.science/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/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":"2026-08-17T03:18:50Z","links":{"resolver":"https://pith.science/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE","bundle":"https://pith.science/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/bundle.json","state":"https://pith.science/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/state.json","well_known_bundle":"https://pith.science/.well-known/pith/TBL2YBHHLXXFHUMSL4IPZCDUIE/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:TBL2YBHHLXXFHUMSL4IPZCDUIE","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":"b9d7d9a65a54a384d30330a6508ab6f23d893949671c3dff2b289b30724ab797","cross_cats_sorted":["astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2019-11-18T15:20:03Z","title_canon_sha256":"e3fe7dd38164be653065d2c9670aa5b2f1c67cf7203d4d1a8320095dd131c788"},"schema_version":"1.0","source":{"id":"1911.07695","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1911.07695","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"arxiv_version","alias_value":"1911.07695v3","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1911.07695","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_12","alias_value":"TBL2YBHHLXXF","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_16","alias_value":"TBL2YBHHLXXFHUMS","created_at":"2026-07-05T01:31:09Z"},{"alias_kind":"pith_short_8","alias_value":"TBL2YBHH","created_at":"2026-07-05T01:31:09Z"}],"graph_snapshots":[{"event_id":"sha256:b6bdcccda8101abf87bd6c54a83bcf0970313f23faa7d9e8c97df22ea6580e5d","target":"graph","created_at":"2026-07-05T01:31:09Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/1911.07695/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In general relativity, isolated black holes are invisible due to an infinitely large redshift of photons propagating from the event horizon to the remote observer. However, the dark shadow (silhouette) of a black hole can be visible on the background of matter radiation lensed by the gravitational field of black holes. The black hole shadow is the celestial sphere projection of the cross section of photon capture by the black hole. If the illuminating background is far behind the black hole (at a distance much greater than the event horizon radius), a classic black hole shadow of a maximal siz","authors_text":"Natalia O. Nazarova, Vyacheslav I. Dokuchaev","cross_cats":["astro-ph.HE"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2019-11-18T15:20:03Z","title":"Silhouettes of invisible black holes"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1911.07695","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":"sha256:06d0a384f82f1a8ca69f0e0e534b52808bbd5b146f3799aec8f316de2368168f","target":"record","created_at":"2026-07-05T01:31:09Z","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":"b9d7d9a65a54a384d30330a6508ab6f23d893949671c3dff2b289b30724ab797","cross_cats_sorted":["astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2019-11-18T15:20:03Z","title_canon_sha256":"e3fe7dd38164be653065d2c9670aa5b2f1c67cf7203d4d1a8320095dd131c788"},"schema_version":"1.0","source":{"id":"1911.07695","kind":"arxiv","version":3}},"canonical_sha256":"9857ac04e75dee53d1925f10fc8874413de3110e905cecb46a69999db42be244","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9857ac04e75dee53d1925f10fc8874413de3110e905cecb46a69999db42be244","first_computed_at":"2026-07-05T01:31:09.085461Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T01:31:09.085461Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"5eXaG9YhWNc3iX7ilKQp2bBamhjU5qwxhmpIgE9P9ypEtvDa8VWjBtZ8uSAeMa7AGUNgjgkkupfMGevnV22cBw==","signature_status":"signed_v1","signed_at":"2026-07-05T01:31:09.085887Z","signed_message":"canonical_sha256_bytes"},"source_id":"1911.07695","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:06d0a384f82f1a8ca69f0e0e534b52808bbd5b146f3799aec8f316de2368168f","sha256:b6bdcccda8101abf87bd6c54a83bcf0970313f23faa7d9e8c97df22ea6580e5d"],"state_sha256":"7a5f5fd260121d02bcee1fb57b6dd5ec0a63d23f4a52e6a989eeb5ecb6cf634f"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"IJwQFDaufMHFMXaBKpIXGUVzO1cLVi3Q+tVOVtjrt2ML4EkrVEpf2mYZCvQdef6u2lolJgk5jOTHEg2emrAJAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-17T03:18:50.713036Z","bundle_sha256":"449e27391180f134b1746d908b775bb761388ee97cdb187243fa9d15aee5efc6"}}