{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2002:RXQFED572X47AEQT2DS3C5YG2W","short_pith_number":"pith:RXQFED57","canonical_record":{"source":{"id":"quant-ph/0207063","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2002-07-10T22:51:18Z","cross_cats_sorted":[],"title_canon_sha256":"76a376fa3b004f3bd70914892f43e0cf5e19a48270290789f552b348c22ad553","abstract_canon_sha256":"06bbadffc9c810b06e4058eb3a54165c5c030a856a1c1dd96860c926689df116"},"schema_version":"1.0"},"canonical_sha256":"8de0520fbfd5f9f01213d0e5b17706d59ba48b6ea20f7683157e4acd7a997fc7","source":{"kind":"arxiv","id":"quant-ph/0207063","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0207063","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0207063v1","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0207063","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_12","alias_value":"RXQFED572X47","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_16","alias_value":"RXQFED572X47AEQT","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_8","alias_value":"RXQFED57","created_at":"2026-07-04T16:36:07Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2002:RXQFED572X47AEQT2DS3C5YG2W","target":"record","payload":{"canonical_record":{"source":{"id":"quant-ph/0207063","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2002-07-10T22:51:18Z","cross_cats_sorted":[],"title_canon_sha256":"76a376fa3b004f3bd70914892f43e0cf5e19a48270290789f552b348c22ad553","abstract_canon_sha256":"06bbadffc9c810b06e4058eb3a54165c5c030a856a1c1dd96860c926689df116"},"schema_version":"1.0"},"canonical_sha256":"8de0520fbfd5f9f01213d0e5b17706d59ba48b6ea20f7683157e4acd7a997fc7","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:36:07.076856Z","signature_b64":"TmFiRjix52Qp3N+ddn+ivVygZysSmgZ5Zu8k1wSejOJyGwTZ26L6MtTP/TOWbN+DVaeMjl8rtCS2iTcYvHnQAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"8de0520fbfd5f9f01213d0e5b17706d59ba48b6ea20f7683157e4acd7a997fc7","last_reissued_at":"2026-07-04T16:36:07.076442Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:36:07.076442Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"quant-ph/0207063","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":"2026-07-04T16:36:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Qbgr1mWsZ04XcuVmorUk4IqrUSLiVy6qifo47nzHBF8h87dUwREy8vx6JSkU+K5UKSbEs1OxPgMPoKzKY8wxDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T16:21:00.012620Z"},"content_sha256":"b3ef34caaefca5a7a0fdc4e9fcdc19700e5ab06eebaa9d9bb3fc859857da3ff2","schema_version":"1.0","event_id":"sha256:b3ef34caaefca5a7a0fdc4e9fcdc19700e5ab06eebaa9d9bb3fc859857da3ff2"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2002:RXQFED572X47AEQT2DS3C5YG2W","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Error prevention scheme with two pairs of qubits","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Chui-ping Yang, Shih-I Chu, Siyuan Han","submitted_at":"2002-07-10T22:51:18Z","abstract_excerpt":"A scheme is presented for protecting one-qubit quantum information against decoherence due to a general environment and local exchange interactions. The scheme operates essentially by distributing information over two pairs of qubits and through error prevention procedures. In the scheme, quantum information is encoded through a decoherence-free subspace for collective phase errors and exchange errors affecting the qubits in pairs; leakage out of the encoding space due to amplitude damping is reduced by quantum Zeno effect. In addition, how to construct decoherence-free states for n-qubit info"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0207063","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/quant-ph/0207063/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":"2026-07-04T16:36:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"XSbUTiEMgwLae7SnEWeH3oTpUDOjnu9kAZQkR4XQ+pVpFO5QxjCsPrMle+rtgp1Rm9crCj7nviHNo6ysf38qBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T16:21:00.013140Z"},"content_sha256":"9ec0cc9a4ea5ff2694a9f4cf4f60a89b226830ca7d97fcecd44fd68970f82dc7","schema_version":"1.0","event_id":"sha256:9ec0cc9a4ea5ff2694a9f4cf4f60a89b226830ca7d97fcecd44fd68970f82dc7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/RXQFED572X47AEQT2DS3C5YG2W/bundle.json","state_url":"https://pith.science/pith/RXQFED572X47AEQT2DS3C5YG2W/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/RXQFED572X47AEQT2DS3C5YG2W/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":"2026-08-03T16:21:00Z","links":{"resolver":"https://pith.science/pith/RXQFED572X47AEQT2DS3C5YG2W","bundle":"https://pith.science/pith/RXQFED572X47AEQT2DS3C5YG2W/bundle.json","state":"https://pith.science/pith/RXQFED572X47AEQT2DS3C5YG2W/state.json","well_known_bundle":"https://pith.science/.well-known/pith/RXQFED572X47AEQT2DS3C5YG2W/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2002:RXQFED572X47AEQT2DS3C5YG2W","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":"06bbadffc9c810b06e4058eb3a54165c5c030a856a1c1dd96860c926689df116","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2002-07-10T22:51:18Z","title_canon_sha256":"76a376fa3b004f3bd70914892f43e0cf5e19a48270290789f552b348c22ad553"},"schema_version":"1.0","source":{"id":"quant-ph/0207063","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0207063","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0207063v1","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0207063","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_12","alias_value":"RXQFED572X47","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_16","alias_value":"RXQFED572X47AEQT","created_at":"2026-07-04T16:36:07Z"},{"alias_kind":"pith_short_8","alias_value":"RXQFED57","created_at":"2026-07-04T16:36:07Z"}],"graph_snapshots":[{"event_id":"sha256:9ec0cc9a4ea5ff2694a9f4cf4f60a89b226830ca7d97fcecd44fd68970f82dc7","target":"graph","created_at":"2026-07-04T16:36:07Z","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/quant-ph/0207063/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"A scheme is presented for protecting one-qubit quantum information against decoherence due to a general environment and local exchange interactions. The scheme operates essentially by distributing information over two pairs of qubits and through error prevention procedures. In the scheme, quantum information is encoded through a decoherence-free subspace for collective phase errors and exchange errors affecting the qubits in pairs; leakage out of the encoding space due to amplitude damping is reduced by quantum Zeno effect. In addition, how to construct decoherence-free states for n-qubit info","authors_text":"Chui-ping Yang, Shih-I Chu, Siyuan Han","cross_cats":[],"headline":"","license":"","primary_cat":"quant-ph","submitted_at":"2002-07-10T22:51:18Z","title":"Error prevention scheme with two pairs of qubits"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0207063","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:b3ef34caaefca5a7a0fdc4e9fcdc19700e5ab06eebaa9d9bb3fc859857da3ff2","target":"record","created_at":"2026-07-04T16:36:07Z","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":"06bbadffc9c810b06e4058eb3a54165c5c030a856a1c1dd96860c926689df116","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2002-07-10T22:51:18Z","title_canon_sha256":"76a376fa3b004f3bd70914892f43e0cf5e19a48270290789f552b348c22ad553"},"schema_version":"1.0","source":{"id":"quant-ph/0207063","kind":"arxiv","version":1}},"canonical_sha256":"8de0520fbfd5f9f01213d0e5b17706d59ba48b6ea20f7683157e4acd7a997fc7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"8de0520fbfd5f9f01213d0e5b17706d59ba48b6ea20f7683157e4acd7a997fc7","first_computed_at":"2026-07-04T16:36:07.076442Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:36:07.076442Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"TmFiRjix52Qp3N+ddn+ivVygZysSmgZ5Zu8k1wSejOJyGwTZ26L6MtTP/TOWbN+DVaeMjl8rtCS2iTcYvHnQAA==","signature_status":"signed_v1","signed_at":"2026-07-04T16:36:07.076856Z","signed_message":"canonical_sha256_bytes"},"source_id":"quant-ph/0207063","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b3ef34caaefca5a7a0fdc4e9fcdc19700e5ab06eebaa9d9bb3fc859857da3ff2","sha256:9ec0cc9a4ea5ff2694a9f4cf4f60a89b226830ca7d97fcecd44fd68970f82dc7"],"state_sha256":"620cba2ff81cd8ec4cde8657c255be0fc7663210e259e3a46e74c38668aba00c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"atea5ZIdwg99i18Tvkr0hrMp4ulXPokgZooWkYMW/ePpLFQKlqk434X5zTaNq5B5L1D7nn1aQQC3o5yuRrtZAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-03T16:21:00.020550Z","bundle_sha256":"1be7effba2901e885858bdd08a28fdb52f8f2598267036ed3d02bc7724437c55"}}