{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2007:MGMPXKN2A7IABHIYDZQLDAMEZU","short_pith_number":"pith:MGMPXKN2","canonical_record":{"source":{"id":"quant-ph/0703036","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2007-03-05T10:45:36Z","cross_cats_sorted":[],"title_canon_sha256":"77e226c51bc8b1a85b744f14ce58654a0b6b919110b3a2d4c6d269c17c7f4778","abstract_canon_sha256":"e86e93f5c0c786305e874797ecfb920422f9a2d43e872a8682f4273ea98d2bc6"},"schema_version":"1.0"},"canonical_sha256":"6198fba9ba07d0009d181e60b18184cd139dbda2bb37d129de79fa186fab1613","source":{"kind":"arxiv","id":"quant-ph/0703036","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0703036","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0703036v2","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0703036","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"pith_short_12","alias_value":"MGMPXKN2A7IA","created_at":"2026-05-18T12:25:55Z"},{"alias_kind":"pith_short_16","alias_value":"MGMPXKN2A7IABHIY","created_at":"2026-05-18T12:25:55Z"},{"alias_kind":"pith_short_8","alias_value":"MGMPXKN2","created_at":"2026-05-18T12:25:55Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2007:MGMPXKN2A7IABHIYDZQLDAMEZU","target":"record","payload":{"canonical_record":{"source":{"id":"quant-ph/0703036","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"quant-ph","submitted_at":"2007-03-05T10:45:36Z","cross_cats_sorted":[],"title_canon_sha256":"77e226c51bc8b1a85b744f14ce58654a0b6b919110b3a2d4c6d269c17c7f4778","abstract_canon_sha256":"e86e93f5c0c786305e874797ecfb920422f9a2d43e872a8682f4273ea98d2bc6"},"schema_version":"1.0"},"canonical_sha256":"6198fba9ba07d0009d181e60b18184cd139dbda2bb37d129de79fa186fab1613","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:20:50.173035Z","signature_b64":"59pborRyR/fKYfOt4ZzZZH8ShxExwWx2wr8+MUs+q/+VwP5wLl8K4uhgvWe2ttWK9ZswizJujJnj+efB3SHTAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6198fba9ba07d0009d181e60b18184cd139dbda2bb37d129de79fa186fab1613","last_reissued_at":"2026-05-18T04:20:50.172302Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:20:50.172302Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"quant-ph/0703036","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":"2026-05-18T04:20:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"L0kgJ0vyENE7J5lx3mhQADW7dJeM2V83TH3/Vhhr+t+0II62urSj+j7MBPvTR1anPMKbInDp/fHUV2w5Cx43DQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T05:38:39.785276Z"},"content_sha256":"f356f78e3b504c4b407e5b4788661b50f769c73f289d66299f80d21d528995a5","schema_version":"1.0","event_id":"sha256:f356f78e3b504c4b407e5b4788661b50f769c73f289d66299f80d21d528995a5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2007:MGMPXKN2A7IABHIYDZQLDAMEZU","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Uncertainty Relations for Positive Operator Valued Measures","license":"","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Serge Massar","submitted_at":"2007-03-05T10:45:36Z","abstract_excerpt":"How much unavoidable randomness is generated by a Positive Operator Valued Measure (POVM)? We address this question using two complementary approaches. First we study the variance of a real variable associated to the POVM outcomes. In this context we introduce an uncertainty operator which measures how much additional noise is introduced by carrying out a POVM rather than a von Neumann measurement. We illustrate this first approach by studying the variances of joint estimates of \\sigma_x and \\sigma_z for spin 1/2 particles. We show that for unbiased measurements the sum of these variances is l"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0703036","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":"2026-05-18T04:20:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+xAmrKtmkn9RbSBDQ7EHNPcZPgpI7HMzVG7tqqQgqXOWMBSwLpsBBCfdPfOE/LvpB8+7lnYgG1ggOc6A0UzdBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T05:38:39.785956Z"},"content_sha256":"9f7b4709bf39601dbe852bc9e3820d062b442930d9c32665439fca591ab5e1c0","schema_version":"1.0","event_id":"sha256:9f7b4709bf39601dbe852bc9e3820d062b442930d9c32665439fca591ab5e1c0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/bundle.json","state_url":"https://pith.science/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/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":"2026-05-27T05:38:39Z","links":{"resolver":"https://pith.science/pith/MGMPXKN2A7IABHIYDZQLDAMEZU","bundle":"https://pith.science/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/bundle.json","state":"https://pith.science/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/state.json","well_known_bundle":"https://pith.science/.well-known/pith/MGMPXKN2A7IABHIYDZQLDAMEZU/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2007:MGMPXKN2A7IABHIYDZQLDAMEZU","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":"e86e93f5c0c786305e874797ecfb920422f9a2d43e872a8682f4273ea98d2bc6","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2007-03-05T10:45:36Z","title_canon_sha256":"77e226c51bc8b1a85b744f14ce58654a0b6b919110b3a2d4c6d269c17c7f4778"},"schema_version":"1.0","source":{"id":"quant-ph/0703036","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"quant-ph/0703036","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"arxiv_version","alias_value":"quant-ph/0703036v2","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.quant-ph/0703036","created_at":"2026-05-18T04:20:50Z"},{"alias_kind":"pith_short_12","alias_value":"MGMPXKN2A7IA","created_at":"2026-05-18T12:25:55Z"},{"alias_kind":"pith_short_16","alias_value":"MGMPXKN2A7IABHIY","created_at":"2026-05-18T12:25:55Z"},{"alias_kind":"pith_short_8","alias_value":"MGMPXKN2","created_at":"2026-05-18T12:25:55Z"}],"graph_snapshots":[{"event_id":"sha256:9f7b4709bf39601dbe852bc9e3820d062b442930d9c32665439fca591ab5e1c0","target":"graph","created_at":"2026-05-18T04:20:50Z","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":"How much unavoidable randomness is generated by a Positive Operator Valued Measure (POVM)? We address this question using two complementary approaches. First we study the variance of a real variable associated to the POVM outcomes. In this context we introduce an uncertainty operator which measures how much additional noise is introduced by carrying out a POVM rather than a von Neumann measurement. We illustrate this first approach by studying the variances of joint estimates of \\sigma_x and \\sigma_z for spin 1/2 particles. We show that for unbiased measurements the sum of these variances is l","authors_text":"Serge Massar","cross_cats":[],"headline":"","license":"","primary_cat":"quant-ph","submitted_at":"2007-03-05T10:45:36Z","title":"Uncertainty Relations for Positive Operator Valued Measures"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"quant-ph/0703036","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:f356f78e3b504c4b407e5b4788661b50f769c73f289d66299f80d21d528995a5","target":"record","created_at":"2026-05-18T04:20:50Z","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":"e86e93f5c0c786305e874797ecfb920422f9a2d43e872a8682f4273ea98d2bc6","cross_cats_sorted":[],"license":"","primary_cat":"quant-ph","submitted_at":"2007-03-05T10:45:36Z","title_canon_sha256":"77e226c51bc8b1a85b744f14ce58654a0b6b919110b3a2d4c6d269c17c7f4778"},"schema_version":"1.0","source":{"id":"quant-ph/0703036","kind":"arxiv","version":2}},"canonical_sha256":"6198fba9ba07d0009d181e60b18184cd139dbda2bb37d129de79fa186fab1613","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6198fba9ba07d0009d181e60b18184cd139dbda2bb37d129de79fa186fab1613","first_computed_at":"2026-05-18T04:20:50.172302Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:20:50.172302Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"59pborRyR/fKYfOt4ZzZZH8ShxExwWx2wr8+MUs+q/+VwP5wLl8K4uhgvWe2ttWK9ZswizJujJnj+efB3SHTAw==","signature_status":"signed_v1","signed_at":"2026-05-18T04:20:50.173035Z","signed_message":"canonical_sha256_bytes"},"source_id":"quant-ph/0703036","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f356f78e3b504c4b407e5b4788661b50f769c73f289d66299f80d21d528995a5","sha256:9f7b4709bf39601dbe852bc9e3820d062b442930d9c32665439fca591ab5e1c0"],"state_sha256":"7cd43bd6eb561d21304b51320fd51597f768ae7f2e0e858f5bc2537c9a1a3664"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"gozQUsTsVIfuKpnQMlpRP8CgnXJoXnhWbQqfhvdIbndhIF+HZ0AP6sxHsWB7PEvO4e/RknkyMx1lMiRYYfDlAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-27T05:38:39.789349Z","bundle_sha256":"7c26ea732cb57195fd9ed1a0f56c22e793702348aea62c22b0e23be332daab4f"}}