{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:3JEIVGTFSQHDHILJ7ARBSO7BZJ","short_pith_number":"pith:3JEIVGTF","canonical_record":{"source":{"id":"1803.01445","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DB","submitted_at":"2018-03-05T00:48:08Z","cross_cats_sorted":[],"title_canon_sha256":"0f452ac9f2561d8a43d3c729e87924c31c223c4bf1696317dddf726e2a59ad50","abstract_canon_sha256":"579176b401973b7253923e712eb7a8485b53a800579cf215be0893dcd2f84ee1"},"schema_version":"1.0"},"canonical_sha256":"da488a9a65940e33a169f822193be1ca60b20c996cb9d092df1da0773d7466a2","source":{"kind":"arxiv","id":"1803.01445","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.01445","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"arxiv_version","alias_value":"1803.01445v1","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.01445","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"pith_short_12","alias_value":"3JEIVGTFSQHD","created_at":"2026-05-18T12:32:02Z"},{"alias_kind":"pith_short_16","alias_value":"3JEIVGTFSQHDHILJ","created_at":"2026-05-18T12:32:02Z"},{"alias_kind":"pith_short_8","alias_value":"3JEIVGTF","created_at":"2026-05-18T12:32:02Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:3JEIVGTFSQHDHILJ7ARBSO7BZJ","target":"record","payload":{"canonical_record":{"source":{"id":"1803.01445","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DB","submitted_at":"2018-03-05T00:48:08Z","cross_cats_sorted":[],"title_canon_sha256":"0f452ac9f2561d8a43d3c729e87924c31c223c4bf1696317dddf726e2a59ad50","abstract_canon_sha256":"579176b401973b7253923e712eb7a8485b53a800579cf215be0893dcd2f84ee1"},"schema_version":"1.0"},"canonical_sha256":"da488a9a65940e33a169f822193be1ca60b20c996cb9d092df1da0773d7466a2","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:22:00.670145Z","signature_b64":"2fvDHZ8iYg2bT31z0VcQPKgOblcsNOmfvTJqzC7yvVKaz5nU8x+wVA0TwSQuP4XhLGOGB0QixMD8W4KFdbjNBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"da488a9a65940e33a169f822193be1ca60b20c996cb9d092df1da0773d7466a2","last_reissued_at":"2026-05-18T00:22:00.669436Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:22:00.669436Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1803.01445","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":"2026-05-18T00:22:00Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ok+TVC45JmFNv4j2hp7Zptco5DMgiVy7qFmxGr0RAFSVqpEtm9/QvVJ7d3D4U9IBbMfLWC4ir939Rn/v6c17DQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T20:26:10.319388Z"},"content_sha256":"31590e38482d7bc84d3f168187ac8380de6b8c12eaeb88e70e1d8d7705d314c2","schema_version":"1.0","event_id":"sha256:31590e38482d7bc84d3f168187ac8380de6b8c12eaeb88e70e1d8d7705d314c2"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:3JEIVGTFSQHDHILJ7ARBSO7BZJ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Universal (and Existential) Nulls","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.DB","authors_text":"Ali Moallemi, G\\\"osta Grahne","submitted_at":"2018-03-05T00:48:08Z","abstract_excerpt":"Incomplete Information research is quite mature when it comes to so called {\\em existential nulls}, where an existential null is a value stored in the database, representing an unknown object. For some reason {\\em universal nulls}, that is, values representing {\\em all} possible objects, have received almost no attention. We remedy the situation in this paper, by showing that a suitable finite representation mechanism, called {\\em Star Cylinders}, handling universal nulls can be developed based on the {\\em Cylindric Set Algebra} of Henkin, Monk and Tarski. We provide a finitary version of the "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.01445","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":"2026-05-18T00:22:00Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"yeI1TLMz5SuILAJdriuHlayhLEbg7VGrBDcCa726k2O4U+cdQRluKYZQ5NUGx48dKHyb4bllvyQLoCiaWkdYCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T20:26:10.319721Z"},"content_sha256":"45f0e0cd818cd5268f44de05302d4196f8d2e74a87a8b1532612713aa26e8012","schema_version":"1.0","event_id":"sha256:45f0e0cd818cd5268f44de05302d4196f8d2e74a87a8b1532612713aa26e8012"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/bundle.json","state_url":"https://pith.science/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/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":"2026-07-04T20:26:10Z","links":{"resolver":"https://pith.science/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ","bundle":"https://pith.science/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/bundle.json","state":"https://pith.science/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/3JEIVGTFSQHDHILJ7ARBSO7BZJ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:3JEIVGTFSQHDHILJ7ARBSO7BZJ","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":"579176b401973b7253923e712eb7a8485b53a800579cf215be0893dcd2f84ee1","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DB","submitted_at":"2018-03-05T00:48:08Z","title_canon_sha256":"0f452ac9f2561d8a43d3c729e87924c31c223c4bf1696317dddf726e2a59ad50"},"schema_version":"1.0","source":{"id":"1803.01445","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.01445","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"arxiv_version","alias_value":"1803.01445v1","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.01445","created_at":"2026-05-18T00:22:00Z"},{"alias_kind":"pith_short_12","alias_value":"3JEIVGTFSQHD","created_at":"2026-05-18T12:32:02Z"},{"alias_kind":"pith_short_16","alias_value":"3JEIVGTFSQHDHILJ","created_at":"2026-05-18T12:32:02Z"},{"alias_kind":"pith_short_8","alias_value":"3JEIVGTF","created_at":"2026-05-18T12:32:02Z"}],"graph_snapshots":[{"event_id":"sha256:45f0e0cd818cd5268f44de05302d4196f8d2e74a87a8b1532612713aa26e8012","target":"graph","created_at":"2026-05-18T00:22:00Z","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":"Incomplete Information research is quite mature when it comes to so called {\\em existential nulls}, where an existential null is a value stored in the database, representing an unknown object. For some reason {\\em universal nulls}, that is, values representing {\\em all} possible objects, have received almost no attention. We remedy the situation in this paper, by showing that a suitable finite representation mechanism, called {\\em Star Cylinders}, handling universal nulls can be developed based on the {\\em Cylindric Set Algebra} of Henkin, Monk and Tarski. We provide a finitary version of the ","authors_text":"Ali Moallemi, G\\\"osta Grahne","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DB","submitted_at":"2018-03-05T00:48:08Z","title":"Universal (and Existential) Nulls"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.01445","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":"sha256:31590e38482d7bc84d3f168187ac8380de6b8c12eaeb88e70e1d8d7705d314c2","target":"record","created_at":"2026-05-18T00:22:00Z","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":"579176b401973b7253923e712eb7a8485b53a800579cf215be0893dcd2f84ee1","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.DB","submitted_at":"2018-03-05T00:48:08Z","title_canon_sha256":"0f452ac9f2561d8a43d3c729e87924c31c223c4bf1696317dddf726e2a59ad50"},"schema_version":"1.0","source":{"id":"1803.01445","kind":"arxiv","version":1}},"canonical_sha256":"da488a9a65940e33a169f822193be1ca60b20c996cb9d092df1da0773d7466a2","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"da488a9a65940e33a169f822193be1ca60b20c996cb9d092df1da0773d7466a2","first_computed_at":"2026-05-18T00:22:00.669436Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:22:00.669436Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"2fvDHZ8iYg2bT31z0VcQPKgOblcsNOmfvTJqzC7yvVKaz5nU8x+wVA0TwSQuP4XhLGOGB0QixMD8W4KFdbjNBg==","signature_status":"signed_v1","signed_at":"2026-05-18T00:22:00.670145Z","signed_message":"canonical_sha256_bytes"},"source_id":"1803.01445","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:31590e38482d7bc84d3f168187ac8380de6b8c12eaeb88e70e1d8d7705d314c2","sha256:45f0e0cd818cd5268f44de05302d4196f8d2e74a87a8b1532612713aa26e8012"],"state_sha256":"558362310e5cc2a7278fff7422c7d1616bbc843fbc716926328007b18d851513"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"eausUqz9KCgC2fBIHNRcuiBuM8omTYDYiYhqiHFx3bgnIsWjkXGzdjHmIRtnHqf/r4Gzf3cHvEERN9NrOhFhAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-04T20:26:10.321511Z","bundle_sha256":"b1f33b8e597ac3875fa0356bb7f8d68e850221f4fe578ee6ef685d2ac743919c"}}