{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2008:YCWUBU5JYE4ELHCKRADPMSET5Z","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":"2558e0fe54105e36bc6c43125f198e7ac80b0e87c15aebaea4c365cdbc9435fb","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2008-07-03T15:30:19Z","title_canon_sha256":"0e9ad9cc1cd8c88bede6bdbc02a03d70bb2a16957f6b67f28f932c44ba513ab2"},"schema_version":"1.0","source":{"id":"0807.0583","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0807.0583","created_at":"2026-05-18T04:05:47Z"},{"alias_kind":"arxiv_version","alias_value":"0807.0583v2","created_at":"2026-05-18T04:05:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0807.0583","created_at":"2026-05-18T04:05:47Z"},{"alias_kind":"pith_short_12","alias_value":"YCWUBU5JYE4E","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_16","alias_value":"YCWUBU5JYE4ELHCK","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_8","alias_value":"YCWUBU5J","created_at":"2026-05-18T12:25:58Z"}],"graph_snapshots":[{"event_id":"sha256:a79fe1cff041e6d6718babb7dc051b5998578bbddf6e748dc2026a900c5e57c4","target":"graph","created_at":"2026-05-18T04:05:47Z","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":"We study in detail a very natural metric for quantum states. This new proposal has two basic ingredients: entropy and purification. The metric for two mixed states is defined as the square root of the entropy of the average of representative purifications of those states. Some basic properties are analyzed and its relation with other distances is investigated. As an illustrative application, the proposed metric is evaluated for 1-qubit mixed states.","authors_text":"J. Sparacino, M. Portesi, P.W. Lamberti","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2008-07-03T15:30:19Z","title":"Natural Metric for Quantum Information Theory"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0807.0583","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:ea74f8d807b8273488d5a4a8864233f672e5df783c3124813a38c142f503740e","target":"record","created_at":"2026-05-18T04:05:47Z","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":"2558e0fe54105e36bc6c43125f198e7ac80b0e87c15aebaea4c365cdbc9435fb","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2008-07-03T15:30:19Z","title_canon_sha256":"0e9ad9cc1cd8c88bede6bdbc02a03d70bb2a16957f6b67f28f932c44ba513ab2"},"schema_version":"1.0","source":{"id":"0807.0583","kind":"arxiv","version":2}},"canonical_sha256":"c0ad40d3a9c138459c4a8806f64893ee7521b3cc915705122e1137360a818d7b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c0ad40d3a9c138459c4a8806f64893ee7521b3cc915705122e1137360a818d7b","first_computed_at":"2026-05-18T04:05:47.753678Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:05:47.753678Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"V9fa3xiVlFmq9e+ESqmmy3XeokWplk05LwmqNK1DpGa35ObgonPCKQWaif/NJnhWGDMNcRQ6PVCRJvaVNVQdCA==","signature_status":"signed_v1","signed_at":"2026-05-18T04:05:47.754219Z","signed_message":"canonical_sha256_bytes"},"source_id":"0807.0583","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ea74f8d807b8273488d5a4a8864233f672e5df783c3124813a38c142f503740e","sha256:a79fe1cff041e6d6718babb7dc051b5998578bbddf6e748dc2026a900c5e57c4"],"state_sha256":"a47f35a4a4ae9b9d37a02dd6fdb7f93abd5bf3490a8522ec1991007a296bc15b"}