{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:MVL6HA7QMC3FMHIT6HWWIARQVF","short_pith_number":"pith:MVL6HA7Q","canonical_record":{"source":{"id":"1811.02079","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-11-05T23:07:33Z","cross_cats_sorted":["astro-ph.GA"],"title_canon_sha256":"72da57e95f27b2d4c139a3c09cc4bf7187b01d0dc7b80a4452e361d5480d7acc","abstract_canon_sha256":"c3c5577b844888d0421ca0e370d32225f21fbc3019607a404c3ebcdad27de954"},"schema_version":"1.0"},"canonical_sha256":"6557e383f060b6561d13f1ed640230a977df2c9741fa0f122532c7c7972d8954","source":{"kind":"arxiv","id":"1811.02079","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1811.02079","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"arxiv_version","alias_value":"1811.02079v1","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1811.02079","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"pith_short_12","alias_value":"MVL6HA7QMC3F","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_16","alias_value":"MVL6HA7QMC3FMHIT","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_8","alias_value":"MVL6HA7Q","created_at":"2026-05-18T12:32:40Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:MVL6HA7QMC3FMHIT6HWWIARQVF","target":"record","payload":{"canonical_record":{"source":{"id":"1811.02079","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-11-05T23:07:33Z","cross_cats_sorted":["astro-ph.GA"],"title_canon_sha256":"72da57e95f27b2d4c139a3c09cc4bf7187b01d0dc7b80a4452e361d5480d7acc","abstract_canon_sha256":"c3c5577b844888d0421ca0e370d32225f21fbc3019607a404c3ebcdad27de954"},"schema_version":"1.0"},"canonical_sha256":"6557e383f060b6561d13f1ed640230a977df2c9741fa0f122532c7c7972d8954","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:56:45.071402Z","signature_b64":"7g4xx5twTqfhXqsGLXpowi7h7DgAj/9U97yG362pL27ZynLYTGxofc1U/ViTYNnH/adols5DtOyjaurOYxkgAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6557e383f060b6561d13f1ed640230a977df2c9741fa0f122532c7c7972d8954","last_reissued_at":"2026-05-17T23:56:45.071001Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:56:45.071001Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1811.02079","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:56:45Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KOZ6M1SMjJjtizbfrhec7cWCSXtjppevj4YYDTp2d1+jLKrTcyV0USuhA5IMuS+5VCrVoJ0KzH/P9mnYEVhsDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T05:01:18.412622Z"},"content_sha256":"b67f62eb70549e530af63100f6b82a4eeb678a2d83ce6250c9a719649b9f7968","schema_version":"1.0","event_id":"sha256:b67f62eb70549e530af63100f6b82a4eeb678a2d83ce6250c9a719649b9f7968"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:MVL6HA7QMC3FMHIT6HWWIARQVF","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Testing General Relativity with the Black Hole Shadow Size and Asymmetry of Sagittarius A*: Limitations from Interstellar Scattering","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.IM","authors_text":"Michael D. Johnson, Ramesh Narayan, Ziyan Zhu","submitted_at":"2018-11-05T23:07:33Z","abstract_excerpt":"The Event Horizon Telescope (EHT), a global 230 GHz VLBI array, achieves an angular resolution of ${\\approx} 20\\,\\mu{\\rm as}$, sufficient to resolve the supermassive black hole Sagittarius A* (Sgr A*). This resolution may soon enable measurement of the black hole \"shadow\" size and asymmetry, predicted to be ${\\approx}50\\,\\mu$as and ${\\lesssim} 3\\,\\mu$as, respectively. Measurements that depart from these values could indicate a violation of the \"no-hair theorem.\" However, refractive scattering by the turbulent ionized interstellar medium distorts the image of Sgr A*, affecting its apparent size"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.02079","kind":"arxiv","version":1},"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":"2026-05-17T23:56:45Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"dUlmCKO1oA/HAfpmHqClUCBdbc1ltpHvdYKje+bU2HyJrTguqMo8YSHNRkCQ6/w/Ra7dPoAUN+ukbhvFYZPzAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T05:01:18.413270Z"},"content_sha256":"4139ef1e8da409b92ef1db8770a18db1bf43267145af38bf35477a15d0fd62e3","schema_version":"1.0","event_id":"sha256:4139ef1e8da409b92ef1db8770a18db1bf43267145af38bf35477a15d0fd62e3"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/bundle.json","state_url":"https://pith.science/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/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":"2026-06-05T05:01:18Z","links":{"resolver":"https://pith.science/pith/MVL6HA7QMC3FMHIT6HWWIARQVF","bundle":"https://pith.science/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/bundle.json","state":"https://pith.science/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/state.json","well_known_bundle":"https://pith.science/.well-known/pith/MVL6HA7QMC3FMHIT6HWWIARQVF/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:MVL6HA7QMC3FMHIT6HWWIARQVF","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":"c3c5577b844888d0421ca0e370d32225f21fbc3019607a404c3ebcdad27de954","cross_cats_sorted":["astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-11-05T23:07:33Z","title_canon_sha256":"72da57e95f27b2d4c139a3c09cc4bf7187b01d0dc7b80a4452e361d5480d7acc"},"schema_version":"1.0","source":{"id":"1811.02079","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1811.02079","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"arxiv_version","alias_value":"1811.02079v1","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1811.02079","created_at":"2026-05-17T23:56:45Z"},{"alias_kind":"pith_short_12","alias_value":"MVL6HA7QMC3F","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_16","alias_value":"MVL6HA7QMC3FMHIT","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_8","alias_value":"MVL6HA7Q","created_at":"2026-05-18T12:32:40Z"}],"graph_snapshots":[{"event_id":"sha256:4139ef1e8da409b92ef1db8770a18db1bf43267145af38bf35477a15d0fd62e3","target":"graph","created_at":"2026-05-17T23:56:45Z","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 (EHT), a global 230 GHz VLBI array, achieves an angular resolution of ${\\approx} 20\\,\\mu{\\rm as}$, sufficient to resolve the supermassive black hole Sagittarius A* (Sgr A*). This resolution may soon enable measurement of the black hole \"shadow\" size and asymmetry, predicted to be ${\\approx}50\\,\\mu$as and ${\\lesssim} 3\\,\\mu$as, respectively. Measurements that depart from these values could indicate a violation of the \"no-hair theorem.\" However, refractive scattering by the turbulent ionized interstellar medium distorts the image of Sgr A*, affecting its apparent size","authors_text":"Michael D. Johnson, Ramesh Narayan, Ziyan Zhu","cross_cats":["astro-ph.GA"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-11-05T23:07:33Z","title":"Testing General Relativity with the Black Hole Shadow Size and Asymmetry of Sagittarius A*: Limitations from Interstellar Scattering"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.02079","kind":"arxiv","version":1},"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:b67f62eb70549e530af63100f6b82a4eeb678a2d83ce6250c9a719649b9f7968","target":"record","created_at":"2026-05-17T23:56:45Z","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":"c3c5577b844888d0421ca0e370d32225f21fbc3019607a404c3ebcdad27de954","cross_cats_sorted":["astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-11-05T23:07:33Z","title_canon_sha256":"72da57e95f27b2d4c139a3c09cc4bf7187b01d0dc7b80a4452e361d5480d7acc"},"schema_version":"1.0","source":{"id":"1811.02079","kind":"arxiv","version":1}},"canonical_sha256":"6557e383f060b6561d13f1ed640230a977df2c9741fa0f122532c7c7972d8954","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6557e383f060b6561d13f1ed640230a977df2c9741fa0f122532c7c7972d8954","first_computed_at":"2026-05-17T23:56:45.071001Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:56:45.071001Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7g4xx5twTqfhXqsGLXpowi7h7DgAj/9U97yG362pL27ZynLYTGxofc1U/ViTYNnH/adols5DtOyjaurOYxkgAQ==","signature_status":"signed_v1","signed_at":"2026-05-17T23:56:45.071402Z","signed_message":"canonical_sha256_bytes"},"source_id":"1811.02079","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b67f62eb70549e530af63100f6b82a4eeb678a2d83ce6250c9a719649b9f7968","sha256:4139ef1e8da409b92ef1db8770a18db1bf43267145af38bf35477a15d0fd62e3"],"state_sha256":"da3182bba896b590518a7b4107bd3927b1f54f978be3122fcbcfb2039b7249ca"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"j/xJdRV3TSVh8SuEe0Y8stWbGB52ZXDMncI9GD+hcQoiPQ9vI+OgEAJGu5hsx0PcNGXnXEw+HdOzRNHvPkQQCA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-05T05:01:18.416353Z","bundle_sha256":"3e0aa71ecf42271c4039b3c855f1667672499cc50f8add751dd1e6ca380f33e0"}}