{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2006:QE3FC4ZFZECQGTXXGY3Z6KEJUS","short_pith_number":"pith:QE3FC4ZF","canonical_record":{"source":{"id":"quant-ph/0608037","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2006-08-04T04:34:05Z","cross_cats_sorted":[],"title_canon_sha256":"91df91b7c26de75df3eb73b7e67166f0fd096c1bf86231a221c5967579e1faa4","abstract_canon_sha256":"774dcafe0a633e15f36c9136baf0391bc15a4ec67c90889ec4d3b91d9acda390"},"schema_version":"1.0"},"canonical_sha256":"8136517325c905034ef736379f2889a4b4592eaba6f8d5892713955376aa7f5e","source":{"kind":"arxiv","id":"quant-ph/0608037","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0608037","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0608037v2","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0608037","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_12","alias_value":"QE3FC4ZFZECQ","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_16","alias_value":"QE3FC4ZFZECQGTXX","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_8","alias_value":"QE3FC4ZF","created_at":"2026-07-04T14:59:08Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2006:QE3FC4ZFZECQGTXXGY3Z6KEJUS","target":"record","payload":{"canonical_record":{"source":{"id":"quant-ph/0608037","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2006-08-04T04:34:05Z","cross_cats_sorted":[],"title_canon_sha256":"91df91b7c26de75df3eb73b7e67166f0fd096c1bf86231a221c5967579e1faa4","abstract_canon_sha256":"774dcafe0a633e15f36c9136baf0391bc15a4ec67c90889ec4d3b91d9acda390"},"schema_version":"1.0"},"canonical_sha256":"8136517325c905034ef736379f2889a4b4592eaba6f8d5892713955376aa7f5e","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T14:59:08.344272Z","signature_b64":"mNYHy/NnkQRvX7byD3jnpaGz6AvomVmD+sigj5fF0PU8fvGAlDi6VMpK+AoyJHIq14kXLXopXsjxiWm2DLVNCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"8136517325c905034ef736379f2889a4b4592eaba6f8d5892713955376aa7f5e","last_reissued_at":"2026-07-04T14:59:08.343865Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T14:59:08.343865Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"quant-ph/0608037","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":"2026-07-04T14:59:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9cUg6Fo4Y6r2m0L8iFeD42ITGmCOXblx4dYZSzF5z7dMaIuQhel5m9J0M9ccqYBcXkDtmum1XxUW9MQeVFvlCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T23:53:54.964262Z"},"content_sha256":"61d4c2c741b812922d28adbe11024a260f2e929a868c94cd789e19faaeabf1f0","schema_version":"1.0","event_id":"sha256:61d4c2c741b812922d28adbe11024a260f2e929a868c94cd789e19faaeabf1f0"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2006:QE3FC4ZFZECQGTXXGY3Z6KEJUS","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Quantum Control of a Single Qubit","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Agata M. Branczyk, Alexei Gilchrist, Andrew C. Doherty, Paulo E. M. F. Mendonca, Stephen D. Bartlett","submitted_at":"2006-08-04T04:34:05Z","abstract_excerpt":"Measurements in quantum mechanics cannot perfectly distinguish all states and necessarily disturb the measured system. We present and analyse a proposal to demonstrate fundamental limits on quantum control of a single qubit arising from these properties of quantum measurements. We consider a qubit prepared in one of two non-orthogonal states and subsequently subjected to dephasing noise. The task is to use measurement and feedback control to attempt to correct the state of the qubit. We demonstrate that projective measurements are not optimal for this task, and that there exists a non-projecti"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0608037","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/0608037/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":"2026-07-04T14:59:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"r/SknRJZPav9FtHpniyod3ulq94CmZP6ZDXnpuHusGmR7a0tXY9t/jb4Ay7kTauvekVclCpeRNxoTBu1JcpAAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-04T23:53:54.964643Z"},"content_sha256":"f372e7b424b973ade6efd2abc817d81048e0d54dfcec0f5fc500dc5f0c4f367e","schema_version":"1.0","event_id":"sha256:f372e7b424b973ade6efd2abc817d81048e0d54dfcec0f5fc500dc5f0c4f367e"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/bundle.json","state_url":"https://pith.science/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/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":"2026-07-04T23:53:54Z","links":{"resolver":"https://pith.science/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS","bundle":"https://pith.science/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/bundle.json","state":"https://pith.science/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/state.json","well_known_bundle":"https://pith.science/.well-known/pith/QE3FC4ZFZECQGTXXGY3Z6KEJUS/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2006:QE3FC4ZFZECQGTXXGY3Z6KEJUS","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":"774dcafe0a633e15f36c9136baf0391bc15a4ec67c90889ec4d3b91d9acda390","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2006-08-04T04:34:05Z","title_canon_sha256":"91df91b7c26de75df3eb73b7e67166f0fd096c1bf86231a221c5967579e1faa4"},"schema_version":"1.0","source":{"id":"quant-ph/0608037","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0608037","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0608037v2","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0608037","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_12","alias_value":"QE3FC4ZFZECQ","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_16","alias_value":"QE3FC4ZFZECQGTXX","created_at":"2026-07-04T14:59:08Z"},{"alias_kind":"pith_short_8","alias_value":"QE3FC4ZF","created_at":"2026-07-04T14:59:08Z"}],"graph_snapshots":[{"event_id":"sha256:f372e7b424b973ade6efd2abc817d81048e0d54dfcec0f5fc500dc5f0c4f367e","target":"graph","created_at":"2026-07-04T14:59:08Z","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/0608037/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Measurements in quantum mechanics cannot perfectly distinguish all states and necessarily disturb the measured system. We present and analyse a proposal to demonstrate fundamental limits on quantum control of a single qubit arising from these properties of quantum measurements. We consider a qubit prepared in one of two non-orthogonal states and subsequently subjected to dephasing noise. The task is to use measurement and feedback control to attempt to correct the state of the qubit. We demonstrate that projective measurements are not optimal for this task, and that there exists a non-projecti","authors_text":"Agata M. Branczyk, Alexei Gilchrist, Andrew C. Doherty, Paulo E. M. F. Mendonca, Stephen D. Bartlett","cross_cats":[],"headline":"","license":"","primary_cat":"quant-ph","submitted_at":"2006-08-04T04:34:05Z","title":"Quantum Control of a Single Qubit"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0608037","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":"sha256:61d4c2c741b812922d28adbe11024a260f2e929a868c94cd789e19faaeabf1f0","target":"record","created_at":"2026-07-04T14:59:08Z","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":"774dcafe0a633e15f36c9136baf0391bc15a4ec67c90889ec4d3b91d9acda390","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2006-08-04T04:34:05Z","title_canon_sha256":"91df91b7c26de75df3eb73b7e67166f0fd096c1bf86231a221c5967579e1faa4"},"schema_version":"1.0","source":{"id":"quant-ph/0608037","kind":"arxiv","version":2}},"canonical_sha256":"8136517325c905034ef736379f2889a4b4592eaba6f8d5892713955376aa7f5e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"8136517325c905034ef736379f2889a4b4592eaba6f8d5892713955376aa7f5e","first_computed_at":"2026-07-04T14:59:08.343865Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T14:59:08.343865Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"mNYHy/NnkQRvX7byD3jnpaGz6AvomVmD+sigj5fF0PU8fvGAlDi6VMpK+AoyJHIq14kXLXopXsjxiWm2DLVNCg==","signature_status":"signed_v1","signed_at":"2026-07-04T14:59:08.344272Z","signed_message":"canonical_sha256_bytes"},"source_id":"quant-ph/0608037","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:61d4c2c741b812922d28adbe11024a260f2e929a868c94cd789e19faaeabf1f0","sha256:f372e7b424b973ade6efd2abc817d81048e0d54dfcec0f5fc500dc5f0c4f367e"],"state_sha256":"dfd750d14756fe0e584f602258ac0ae9b7bed950ec4746c41c455039d44c8dc1"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"HOovu8NmBwjodh+YwHEVeD4uOO5QN4nAwBHI6vJaCt4Xy902JeLOX+MQ37gw1l6aTtnxZjsqDX2pcJm7anJBCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-04T23:53:54.966611Z","bundle_sha256":"d94bd78dbceee4d81c3ac18123267b61b16100dcc3c55aa96ce43f13e06502be"}}