{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:1999:ARDIZBPHXFF3SAH6VS6J3YW2GB","short_pith_number":"pith:ARDIZBPH","schema_version":"1.0","canonical_sha256":"04468c85e7b94bb900feacbc9de2da3072cbb6aab3a977a488cdbb508f1b5131","source":{"kind":"arxiv","id":"quant-ph/9912089","version":2},"attestation_state":"computed","paper":{"title":"Separability of entangled q-bit pairs","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Berthold-Georg Englert, Nasser Metwally","submitted_at":"1999-12-18T18:57:09Z","abstract_excerpt":"The state of an entangled q-bit pair is specified by 15 numerical parameters that are naturally regarded as the components of two 3-vectors and a $3\\times3$-dyadic. There are easy-to-use criteria to check whether a given pair of 3-vectors plus a dyadic specify a 2-q-bit state; and if they do, whether the state is entangled; and if it is, whether it is a separable state. Some progress has been made in the search for analytical expressions for the degree of separability. We report, in particular, the answer in the case of vanishing 3-vectors."},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"quant-ph/9912089","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"1999-12-18T18:57:09Z","cross_cats_sorted":[],"title_canon_sha256":"bb57bb1e2784f9c0275d606afeb485cef27426c630a3e89528c6b0d152f9a086","abstract_canon_sha256":"12fbf90cd4dea944f7a4d75e62bb7c667119069f6a6020df6eb5b108bd32324c"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:37:52.171981Z","signature_b64":"FxAWh70SdehN3c0iF7ElXIGI/Uu/7bHv3BrhuF+1ZLEmoIFSB+xOqas6RjsrJxsVzTMzCuo1bXjw2y0HuYuiCw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"04468c85e7b94bb900feacbc9de2da3072cbb6aab3a977a488cdbb508f1b5131","last_reissued_at":"2026-05-18T01:37:52.171209Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:37:52.171209Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Separability of entangled q-bit pairs","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Berthold-Georg Englert, Nasser Metwally","submitted_at":"1999-12-18T18:57:09Z","abstract_excerpt":"The state of an entangled q-bit pair is specified by 15 numerical parameters that are naturally regarded as the components of two 3-vectors and a $3\\times3$-dyadic. There are easy-to-use criteria to check whether a given pair of 3-vectors plus a dyadic specify a 2-q-bit state; and if they do, whether the state is entangled; and if it is, whether it is a separable state. Some progress has been made in the search for analytical expressions for the degree of separability. We report, in particular, the answer in the case of vanishing 3-vectors."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/9912089","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/9912089","created_at":"2026-05-18T01:37:52.171310+00:00"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/9912089v2","created_at":"2026-05-18T01:37:52.171310+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/9912089","created_at":"2026-05-18T01:37:52.171310+00:00"},{"alias_kind":"pith_short_12","alias_value":"ARDIZBPHXFF3","created_at":"2026-05-18T12:25:49.038998+00:00"},{"alias_kind":"pith_short_16","alias_value":"ARDIZBPHXFF3SAH6","created_at":"2026-05-18T12:25:49.038998+00:00"},{"alias_kind":"pith_short_8","alias_value":"ARDIZBPH","created_at":"2026-05-18T12:25:49.038998+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB","json":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB.json","graph_json":"https://pith.science/api/pith-number/ARDIZBPHXFF3SAH6VS6J3YW2GB/graph.json","events_json":"https://pith.science/api/pith-number/ARDIZBPHXFF3SAH6VS6J3YW2GB/events.json","paper":"https://pith.science/paper/ARDIZBPH"},"agent_actions":{"view_html":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB","download_json":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB.json","view_paper":"https://pith.science/paper/ARDIZBPH","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=quant-ph/9912089&json=true","fetch_graph":"https://pith.science/api/pith-number/ARDIZBPHXFF3SAH6VS6J3YW2GB/graph.json","fetch_events":"https://pith.science/api/pith-number/ARDIZBPHXFF3SAH6VS6J3YW2GB/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB/action/timestamp_anchor","attest_storage":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB/action/storage_attestation","attest_author":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB/action/author_attestation","sign_citation":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB/action/citation_signature","submit_replication":"https://pith.science/pith/ARDIZBPHXFF3SAH6VS6J3YW2GB/action/replication_record"}},"created_at":"2026-05-18T01:37:52.171310+00:00","updated_at":"2026-05-18T01:37:52.171310+00:00"}