{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:JRQZ45DKPVEJCXDMKAPNU2TQ5G","short_pith_number":"pith:JRQZ45DK","canonical_record":{"source":{"id":"1508.00458","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-08-03T15:51:01Z","cross_cats_sorted":[],"title_canon_sha256":"97fa5f4311c4af2a420f59bfc6447391a6f59a5e27a476ffe100b2d31d5b5e17","abstract_canon_sha256":"9b502c952647cdaba5485ef2a60a3b75872cb4c51db6a06cadc87bea7487129e"},"schema_version":"1.0"},"canonical_sha256":"4c619e746a7d48915c6c501eda6a70e9bd5fb0e088adcd72b8afada032707c19","source":{"kind":"arxiv","id":"1508.00458","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1508.00458","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"arxiv_version","alias_value":"1508.00458v1","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1508.00458","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"pith_short_12","alias_value":"JRQZ45DKPVEJ","created_at":"2026-05-18T12:29:27Z"},{"alias_kind":"pith_short_16","alias_value":"JRQZ45DKPVEJCXDM","created_at":"2026-05-18T12:29:27Z"},{"alias_kind":"pith_short_8","alias_value":"JRQZ45DK","created_at":"2026-05-18T12:29:27Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:JRQZ45DKPVEJCXDMKAPNU2TQ5G","target":"record","payload":{"canonical_record":{"source":{"id":"1508.00458","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-08-03T15:51:01Z","cross_cats_sorted":[],"title_canon_sha256":"97fa5f4311c4af2a420f59bfc6447391a6f59a5e27a476ffe100b2d31d5b5e17","abstract_canon_sha256":"9b502c952647cdaba5485ef2a60a3b75872cb4c51db6a06cadc87bea7487129e"},"schema_version":"1.0"},"canonical_sha256":"4c619e746a7d48915c6c501eda6a70e9bd5fb0e088adcd72b8afada032707c19","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:23:39.874018Z","signature_b64":"Q6dE4Jr6Y3vd4whdWr8XKycEJw4D2j2EZOKeOI4aE51TAXmQA8h7kuhTYBvwvhBycxhT/J3dqBM+9tJ5f9pxBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"4c619e746a7d48915c6c501eda6a70e9bd5fb0e088adcd72b8afada032707c19","last_reissued_at":"2026-05-18T01:23:39.873394Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:23:39.873394Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1508.00458","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":"2026-05-18T01:23:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"63zW+DSVrPRX4TR8qEhBS+MfmoEp16OnE2jDBILODPAcCLZDOfsiL9btDnz+ZE9KmDsR/BEVJapsffPqa2vzDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T18:28:27.188012Z"},"content_sha256":"b1f5d450aef303c10801d1c22a73ed7ccc98660b58c97344d33b6b7a04f76d31","schema_version":"1.0","event_id":"sha256:b1f5d450aef303c10801d1c22a73ed7ccc98660b58c97344d33b6b7a04f76d31"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:JRQZ45DKPVEJCXDMKAPNU2TQ5G","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"On the convex structure of process POVMs","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Anna Jencova","submitted_at":"2015-08-03T15:51:01Z","abstract_excerpt":"Measurements on quantum channels are described by so-called process operator valued measures, or process POVMs. We study implementing schemes of extremal process POVMs. As it turns out, the corresponding measurement must satisfy certain extremality property, which is stronger that the usual extremality given by the convex structure. This property motivates the introduction and investigation of the A-convex structure of POVMs, which generalizes both the usual convex and C*-convex structure. We show that extremal points and faces of the set of process POVMs are closely related to A-extremal poin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.00458","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":""},"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":"2026-05-18T01:23:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"aKZk+wuGmJH3aDfzgZlTQ+1mbsOhMJY9iGz3HD8tD6F0tJdmx43FhxwJA8ukEi9R9PQkAq31dCPE7JCqtTG1AA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T18:28:27.188738Z"},"content_sha256":"6669284674ee1dd2ddd71b7eb9a19c9902bbe5c283c9568f54bd22ece135d8e2","schema_version":"1.0","event_id":"sha256:6669284674ee1dd2ddd71b7eb9a19c9902bbe5c283c9568f54bd22ece135d8e2"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/bundle.json","state_url":"https://pith.science/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/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":"2026-05-28T18:28:27Z","links":{"resolver":"https://pith.science/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G","bundle":"https://pith.science/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/bundle.json","state":"https://pith.science/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/state.json","well_known_bundle":"https://pith.science/.well-known/pith/JRQZ45DKPVEJCXDMKAPNU2TQ5G/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:JRQZ45DKPVEJCXDMKAPNU2TQ5G","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":"9b502c952647cdaba5485ef2a60a3b75872cb4c51db6a06cadc87bea7487129e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-08-03T15:51:01Z","title_canon_sha256":"97fa5f4311c4af2a420f59bfc6447391a6f59a5e27a476ffe100b2d31d5b5e17"},"schema_version":"1.0","source":{"id":"1508.00458","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1508.00458","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"arxiv_version","alias_value":"1508.00458v1","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1508.00458","created_at":"2026-05-18T01:23:39Z"},{"alias_kind":"pith_short_12","alias_value":"JRQZ45DKPVEJ","created_at":"2026-05-18T12:29:27Z"},{"alias_kind":"pith_short_16","alias_value":"JRQZ45DKPVEJCXDM","created_at":"2026-05-18T12:29:27Z"},{"alias_kind":"pith_short_8","alias_value":"JRQZ45DK","created_at":"2026-05-18T12:29:27Z"}],"graph_snapshots":[{"event_id":"sha256:6669284674ee1dd2ddd71b7eb9a19c9902bbe5c283c9568f54bd22ece135d8e2","target":"graph","created_at":"2026-05-18T01:23:39Z","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":"Measurements on quantum channels are described by so-called process operator valued measures, or process POVMs. We study implementing schemes of extremal process POVMs. As it turns out, the corresponding measurement must satisfy certain extremality property, which is stronger that the usual extremality given by the convex structure. This property motivates the introduction and investigation of the A-convex structure of POVMs, which generalizes both the usual convex and C*-convex structure. We show that extremal points and faces of the set of process POVMs are closely related to A-extremal poin","authors_text":"Anna Jencova","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-08-03T15:51:01Z","title":"On the convex structure of process POVMs"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.00458","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:b1f5d450aef303c10801d1c22a73ed7ccc98660b58c97344d33b6b7a04f76d31","target":"record","created_at":"2026-05-18T01:23:39Z","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":"9b502c952647cdaba5485ef2a60a3b75872cb4c51db6a06cadc87bea7487129e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2015-08-03T15:51:01Z","title_canon_sha256":"97fa5f4311c4af2a420f59bfc6447391a6f59a5e27a476ffe100b2d31d5b5e17"},"schema_version":"1.0","source":{"id":"1508.00458","kind":"arxiv","version":1}},"canonical_sha256":"4c619e746a7d48915c6c501eda6a70e9bd5fb0e088adcd72b8afada032707c19","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"4c619e746a7d48915c6c501eda6a70e9bd5fb0e088adcd72b8afada032707c19","first_computed_at":"2026-05-18T01:23:39.873394Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:23:39.873394Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Q6dE4Jr6Y3vd4whdWr8XKycEJw4D2j2EZOKeOI4aE51TAXmQA8h7kuhTYBvwvhBycxhT/J3dqBM+9tJ5f9pxBg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:23:39.874018Z","signed_message":"canonical_sha256_bytes"},"source_id":"1508.00458","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b1f5d450aef303c10801d1c22a73ed7ccc98660b58c97344d33b6b7a04f76d31","sha256:6669284674ee1dd2ddd71b7eb9a19c9902bbe5c283c9568f54bd22ece135d8e2"],"state_sha256":"09f4d2b07b498b9e68e49419222cf8434103cc4f9482ebce13b86611b3bdc7be"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"RjNQBVpjpIoZ5xxPchiEsEMW9GL1gDZXVegMjPqGbA9RqbSBmCXKVi2MuWZnGxw0TA45efoeBbrpKfebs7uqBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T18:28:27.192810Z","bundle_sha256":"8989c5990e0bbc9d18005f74e39aa08cd5860487757189f6b965cab38973b4d7"}}