{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:1997:QQFT2DFDYZBUP6YGNDPOU4JDQX","short_pith_number":"pith:QQFT2DFD","canonical_record":{"source":{"id":"quant-ph/9705046","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"1997-05-27T07:39:51Z","cross_cats_sorted":[],"title_canon_sha256":"7b7e5b6bed70474204fa523471c9bc4f30095a1d264347eeec11b8c56003ec98","abstract_canon_sha256":"8298d4df585d681fbbc19dde7a33910d037c97a1f477ed6358fd8feaf322a55d"},"schema_version":"1.0"},"canonical_sha256":"840b3d0ca3c64347fb0668deea712385cec4eb7d47f3fce078c6ed81d2a98ad8","source":{"kind":"arxiv","id":"quant-ph/9705046","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/9705046","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/9705046v2","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/9705046","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_12","alias_value":"QQFT2DFDYZBU","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_16","alias_value":"QQFT2DFDYZBUP6YG","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_8","alias_value":"QQFT2DFD","created_at":"2026-07-04T15:36:42Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:1997:QQFT2DFDYZBUP6YGNDPOU4JDQX","target":"record","payload":{"canonical_record":{"source":{"id":"quant-ph/9705046","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"1997-05-27T07:39:51Z","cross_cats_sorted":[],"title_canon_sha256":"7b7e5b6bed70474204fa523471c9bc4f30095a1d264347eeec11b8c56003ec98","abstract_canon_sha256":"8298d4df585d681fbbc19dde7a33910d037c97a1f477ed6358fd8feaf322a55d"},"schema_version":"1.0"},"canonical_sha256":"840b3d0ca3c64347fb0668deea712385cec4eb7d47f3fce078c6ed81d2a98ad8","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T15:36:42.056902Z","signature_b64":"6rR3JYzbP3pc1RzmZQM2ox5d0SXowzWevcg3dGgDy+t3bPEqEUXuwXib/robXvG+u7ARGDhDfV5/OBOrPhkJAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"840b3d0ca3c64347fb0668deea712385cec4eb7d47f3fce078c6ed81d2a98ad8","last_reissued_at":"2026-07-04T15:36:42.056476Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T15:36:42.056476Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"quant-ph/9705046","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":"2026-07-04T15:36:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"FBv6BO3nI6cg0M54oO7sFYFEOgw4QEkpVUw4y3GamPwrG9WHM9zhogYzh8DFXcs3/6Om6bwKUUYNLaO+kL0hBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-05T00:25:06.011912Z"},"content_sha256":"7f5d15597f605270ba876b6605269b152eb6bd2a9567ad22289cf76e628aabad","schema_version":"1.0","event_id":"sha256:7f5d15597f605270ba876b6605269b152eb6bd2a9567ad22289cf76e628aabad"},{"event_type":"graph_snapshot","subject_pith_number":"pith:1997:QQFT2DFDYZBUP6YGNDPOU4JDQX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Optimal Quantum Cloning Machines","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"N. Gisin, S. Massar","submitted_at":"1997-05-27T07:39:51Z","abstract_excerpt":"We present Quantum Cloning Machines (QCM) that transform N identical qubits into $M>N$ identical copies and we prove that the fidelity (quality) of these copies is optimal. The connection between cloning and measurement is discussed in detail. When the number of clones M tends towards infinity, the fidelity of each clone tends towards the optimal fidelity that can be obtained by a measurement on the input qubits. More generally, the QCM are universal devices to translate quantum information into classical information."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/9705046","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/quant-ph/9705046/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":"2026-07-04T15:36:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"iMv5iKuarEhuujjS0CUvWaH2d/HPPa4h6Lyr5kaMI4h95ePi93CFB/Kgb15+5pqDB7c6Jqz7kD0QtdW7I7gvDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-05T00:25:06.012414Z"},"content_sha256":"16a3d3bffeccf5ca7378d6236f8fa3c100ef9d484712266da92632400024a114","schema_version":"1.0","event_id":"sha256:16a3d3bffeccf5ca7378d6236f8fa3c100ef9d484712266da92632400024a114"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/bundle.json","state_url":"https://pith.science/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/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":"2026-08-05T00:25:06Z","links":{"resolver":"https://pith.science/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX","bundle":"https://pith.science/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/bundle.json","state":"https://pith.science/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/QQFT2DFDYZBUP6YGNDPOU4JDQX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:1997:QQFT2DFDYZBUP6YGNDPOU4JDQX","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":"8298d4df585d681fbbc19dde7a33910d037c97a1f477ed6358fd8feaf322a55d","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"1997-05-27T07:39:51Z","title_canon_sha256":"7b7e5b6bed70474204fa523471c9bc4f30095a1d264347eeec11b8c56003ec98"},"schema_version":"1.0","source":{"id":"quant-ph/9705046","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/9705046","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/9705046v2","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/9705046","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_12","alias_value":"QQFT2DFDYZBU","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_16","alias_value":"QQFT2DFDYZBUP6YG","created_at":"2026-07-04T15:36:42Z"},{"alias_kind":"pith_short_8","alias_value":"QQFT2DFD","created_at":"2026-07-04T15:36:42Z"}],"graph_snapshots":[{"event_id":"sha256:16a3d3bffeccf5ca7378d6236f8fa3c100ef9d484712266da92632400024a114","target":"graph","created_at":"2026-07-04T15:36:42Z","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/9705046/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We present Quantum Cloning Machines (QCM) that transform N identical qubits into $M>N$ identical copies and we prove that the fidelity (quality) of these copies is optimal. The connection between cloning and measurement is discussed in detail. When the number of clones M tends towards infinity, the fidelity of each clone tends towards the optimal fidelity that can be obtained by a measurement on the input qubits. More generally, the QCM are universal devices to translate quantum information into classical information.","authors_text":"N. Gisin, S. Massar","cross_cats":[],"headline":"","license":"","primary_cat":"quant-ph","submitted_at":"1997-05-27T07:39:51Z","title":"Optimal Quantum Cloning Machines"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/9705046","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":"sha256:7f5d15597f605270ba876b6605269b152eb6bd2a9567ad22289cf76e628aabad","target":"record","created_at":"2026-07-04T15:36:42Z","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":"8298d4df585d681fbbc19dde7a33910d037c97a1f477ed6358fd8feaf322a55d","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"1997-05-27T07:39:51Z","title_canon_sha256":"7b7e5b6bed70474204fa523471c9bc4f30095a1d264347eeec11b8c56003ec98"},"schema_version":"1.0","source":{"id":"quant-ph/9705046","kind":"arxiv","version":2}},"canonical_sha256":"840b3d0ca3c64347fb0668deea712385cec4eb7d47f3fce078c6ed81d2a98ad8","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"840b3d0ca3c64347fb0668deea712385cec4eb7d47f3fce078c6ed81d2a98ad8","first_computed_at":"2026-07-04T15:36:42.056476Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T15:36:42.056476Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"6rR3JYzbP3pc1RzmZQM2ox5d0SXowzWevcg3dGgDy+t3bPEqEUXuwXib/robXvG+u7ARGDhDfV5/OBOrPhkJAg==","signature_status":"signed_v1","signed_at":"2026-07-04T15:36:42.056902Z","signed_message":"canonical_sha256_bytes"},"source_id":"quant-ph/9705046","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:7f5d15597f605270ba876b6605269b152eb6bd2a9567ad22289cf76e628aabad","sha256:16a3d3bffeccf5ca7378d6236f8fa3c100ef9d484712266da92632400024a114"],"state_sha256":"c4c6464f28fcd0f58bb607893bfaa73768438ef151db5a690df8be8edbd509bb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8JR1xmFsM9tUy63S3xiuJGcA2E1d+draeWpZoYjwlU9R2maNvBejbi+jOsPNxl2PfkCYnbVK9HRNLxpTgWvkDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-05T00:25:06.020941Z","bundle_sha256":"cd2f49dcfa7ef5f41b83be08c74030ed7bb0c70e3f0321e08120f6b0833ee6b6"}}