{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2003:UDRNJVYRR4AYIBMVHZ6TF2L7QV","short_pith_number":"pith:UDRNJVYR","canonical_record":{"source":{"id":"quant-ph/0309131","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2003-09-17T15:27:37Z","cross_cats_sorted":["cond-mat"],"title_canon_sha256":"e6a2d8abe0b8439e8792eec1a3f6f73beb35d367149cd8f216c4ad310189ad8a","abstract_canon_sha256":"bf3828e25d4c0d9b8903325e893de8a75063a8dfec3b910a15a8fa9dd36d78ae"},"schema_version":"1.0"},"canonical_sha256":"a0e2d4d7118f018405953e7d32e97f8551d95312fa3053bbf76dcb947d192cc7","source":{"kind":"arxiv","id":"quant-ph/0309131","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0309131","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0309131v2","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0309131","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"pith_short_12","alias_value":"UDRNJVYRR4AY","created_at":"2026-05-18T12:25:52Z"},{"alias_kind":"pith_short_16","alias_value":"UDRNJVYRR4AYIBMV","created_at":"2026-05-18T12:25:52Z"},{"alias_kind":"pith_short_8","alias_value":"UDRNJVYR","created_at":"2026-05-18T12:25:52Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2003:UDRNJVYRR4AYIBMVHZ6TF2L7QV","target":"record","payload":{"canonical_record":{"source":{"id":"quant-ph/0309131","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2003-09-17T15:27:37Z","cross_cats_sorted":["cond-mat"],"title_canon_sha256":"e6a2d8abe0b8439e8792eec1a3f6f73beb35d367149cd8f216c4ad310189ad8a","abstract_canon_sha256":"bf3828e25d4c0d9b8903325e893de8a75063a8dfec3b910a15a8fa9dd36d78ae"},"schema_version":"1.0"},"canonical_sha256":"a0e2d4d7118f018405953e7d32e97f8551d95312fa3053bbf76dcb947d192cc7","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:05:03.831017Z","signature_b64":"m5zu2hpDLdHGFo0iPS6cizb7tiHHCpR6MIG/Re7d0+2Q1PSoRv1DPCB61FJNA9QsfCqfM9qMz6rvNoahyoHmDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a0e2d4d7118f018405953e7d32e97f8551d95312fa3053bbf76dcb947d192cc7","last_reissued_at":"2026-05-18T01:05:03.830284Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:05:03.830284Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"quant-ph/0309131","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":"2026-05-18T01:05:03Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"J8ZaacEiAUWJX21RTWpiRfrAzal1O15H3pwtVcbxNOGckZkSRFDeW6bv1czYwo5UtkefDrZV5/6t9ShPI8ZxAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-30T20:22:57.089328Z"},"content_sha256":"1a2606167a62dc0f0bd83e4ef8567280a352053a643b1b91aa7063b44e046581","schema_version":"1.0","event_id":"sha256:1a2606167a62dc0f0bd83e4ef8567280a352053a643b1b91aa7063b44e046581"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2003:UDRNJVYRR4AYIBMVHZ6TF2L7QV","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Perfect state transfer in quantum spin networks","license":"","headline":"","cross_cats":["cond-mat"],"primary_cat":"quant-ph","authors_text":"Andrew J. Landahl, Artur Ekert, Matthias Christandl, Nilanjana Datta","submitted_at":"2003-09-17T15:27:37Z","abstract_excerpt":"We propose a class of qubit networks that admit perfect transfer of any quantum state in a fixed period of time. Unlike many other schemes for quantum computation and communication, these networks do not require qubit couplings to be switched on and off. When restricted to N-qubit spin networks of identical qubit couplings, we show that 2 log_3 N is the maximal perfect communication distance for hypercube geometries. Moreover, if one allows fixed but different couplings between the qubits then perfect state transfer can be achieved over arbitrarily long distances in a linear chain."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0309131","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":"2026-05-18T01:05:03Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"yYLep5tTF+RjB6c8HdLi+fs4mF3JJSiFIT9X6wTl7EK++sVYwFvWk+HQGfWnz6QNIfBfK/HRccRb8szmjOfdBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-30T20:22:57.089700Z"},"content_sha256":"989dafe86f7bb9eced0b59945eb03dd0e585a6d9a28fa1fa02c22fb919a776a5","schema_version":"1.0","event_id":"sha256:989dafe86f7bb9eced0b59945eb03dd0e585a6d9a28fa1fa02c22fb919a776a5"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/bundle.json","state_url":"https://pith.science/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/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":"2026-06-30T20:22:57Z","links":{"resolver":"https://pith.science/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV","bundle":"https://pith.science/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/bundle.json","state":"https://pith.science/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UDRNJVYRR4AYIBMVHZ6TF2L7QV/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2003:UDRNJVYRR4AYIBMVHZ6TF2L7QV","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":"bf3828e25d4c0d9b8903325e893de8a75063a8dfec3b910a15a8fa9dd36d78ae","cross_cats_sorted":["cond-mat"],"license":"","primary_cat":"quant-ph","submitted_at":"2003-09-17T15:27:37Z","title_canon_sha256":"e6a2d8abe0b8439e8792eec1a3f6f73beb35d367149cd8f216c4ad310189ad8a"},"schema_version":"1.0","source":{"id":"quant-ph/0309131","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0309131","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0309131v2","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0309131","created_at":"2026-05-18T01:05:03Z"},{"alias_kind":"pith_short_12","alias_value":"UDRNJVYRR4AY","created_at":"2026-05-18T12:25:52Z"},{"alias_kind":"pith_short_16","alias_value":"UDRNJVYRR4AYIBMV","created_at":"2026-05-18T12:25:52Z"},{"alias_kind":"pith_short_8","alias_value":"UDRNJVYR","created_at":"2026-05-18T12:25:52Z"}],"graph_snapshots":[{"event_id":"sha256:989dafe86f7bb9eced0b59945eb03dd0e585a6d9a28fa1fa02c22fb919a776a5","target":"graph","created_at":"2026-05-18T01:05:03Z","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":"We propose a class of qubit networks that admit perfect transfer of any quantum state in a fixed period of time. Unlike many other schemes for quantum computation and communication, these networks do not require qubit couplings to be switched on and off. When restricted to N-qubit spin networks of identical qubit couplings, we show that 2 log_3 N is the maximal perfect communication distance for hypercube geometries. Moreover, if one allows fixed but different couplings between the qubits then perfect state transfer can be achieved over arbitrarily long distances in a linear chain.","authors_text":"Andrew J. Landahl, Artur Ekert, Matthias Christandl, Nilanjana Datta","cross_cats":["cond-mat"],"headline":"","license":"","primary_cat":"quant-ph","submitted_at":"2003-09-17T15:27:37Z","title":"Perfect state transfer in quantum spin networks"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0309131","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":"sha256:1a2606167a62dc0f0bd83e4ef8567280a352053a643b1b91aa7063b44e046581","target":"record","created_at":"2026-05-18T01:05:03Z","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":"bf3828e25d4c0d9b8903325e893de8a75063a8dfec3b910a15a8fa9dd36d78ae","cross_cats_sorted":["cond-mat"],"license":"","primary_cat":"quant-ph","submitted_at":"2003-09-17T15:27:37Z","title_canon_sha256":"e6a2d8abe0b8439e8792eec1a3f6f73beb35d367149cd8f216c4ad310189ad8a"},"schema_version":"1.0","source":{"id":"quant-ph/0309131","kind":"arxiv","version":2}},"canonical_sha256":"a0e2d4d7118f018405953e7d32e97f8551d95312fa3053bbf76dcb947d192cc7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a0e2d4d7118f018405953e7d32e97f8551d95312fa3053bbf76dcb947d192cc7","first_computed_at":"2026-05-18T01:05:03.830284Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:05:03.830284Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"m5zu2hpDLdHGFo0iPS6cizb7tiHHCpR6MIG/Re7d0+2Q1PSoRv1DPCB61FJNA9QsfCqfM9qMz6rvNoahyoHmDg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:05:03.831017Z","signed_message":"canonical_sha256_bytes"},"source_id":"quant-ph/0309131","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1a2606167a62dc0f0bd83e4ef8567280a352053a643b1b91aa7063b44e046581","sha256:989dafe86f7bb9eced0b59945eb03dd0e585a6d9a28fa1fa02c22fb919a776a5"],"state_sha256":"e615e0e5c12d73dceb872c830794cda337c3f61b6361260e1561ba20e586a3ac"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QcVko+afhM6FRS05Xc1LabUZpT4neFDmJ66/GV2vafhsQeQadBJdS41rmpF7MiauPcqBn/uQp/RrFs8yQ2nbBg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-30T20:22:57.091939Z","bundle_sha256":"a6a92f20888da877c9c65de74793691f434dfcf476aeec3c59ec3ee1567de4ff"}}