{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:KXIJOL67E4WNHQ2R7U2KK2Z4AR","short_pith_number":"pith:KXIJOL67","canonical_record":{"source":{"id":"1312.6160","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-12-20T22:00:54Z","cross_cats_sorted":[],"title_canon_sha256":"45ca7da228fc9e56c20259423e65ebfb827769f5206dcba2da14a0ff456c5202","abstract_canon_sha256":"a23587027add0683eb3d531b36d4413bf68f42d9185613b58c02ebd71d1b223b"},"schema_version":"1.0"},"canonical_sha256":"55d0972fdf272cd3c351fd34a56b3c046fd6378dc14837f14401ab35fac3f5a2","source":{"kind":"arxiv","id":"1312.6160","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1312.6160","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"arxiv_version","alias_value":"1312.6160v1","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1312.6160","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"pith_short_12","alias_value":"KXIJOL67E4WN","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_16","alias_value":"KXIJOL67E4WNHQ2R","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_8","alias_value":"KXIJOL67","created_at":"2026-05-18T12:27:51Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:KXIJOL67E4WNHQ2R7U2KK2Z4AR","target":"record","payload":{"canonical_record":{"source":{"id":"1312.6160","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-12-20T22:00:54Z","cross_cats_sorted":[],"title_canon_sha256":"45ca7da228fc9e56c20259423e65ebfb827769f5206dcba2da14a0ff456c5202","abstract_canon_sha256":"a23587027add0683eb3d531b36d4413bf68f42d9185613b58c02ebd71d1b223b"},"schema_version":"1.0"},"canonical_sha256":"55d0972fdf272cd3c351fd34a56b3c046fd6378dc14837f14401ab35fac3f5a2","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:04:05.895270Z","signature_b64":"+uPRNiW9CyPLeQheINZumj5fy0EhpQTJbFH7jW+VUxOOHJIm7hFXc2e9XIYvrSuzZOjyoktvAsD+WFgYLQa3Aw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"55d0972fdf272cd3c351fd34a56b3c046fd6378dc14837f14401ab35fac3f5a2","last_reissued_at":"2026-05-18T03:04:05.894578Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:04:05.894578Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1312.6160","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":"2026-05-18T03:04:05Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"R/bGFz50WmZ3sz32l1yH4crjk8iXMbHJ3jCkIH0z33SEu6U8/bL9mKmCwnpZ1/EfFy2XBVmwQg9UpBeqvwuVAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T14:15:51.688244Z"},"content_sha256":"02ebe1b52f99fc8b00608f639a20ffcc0d75492a7f269e75c344bcdea49ecef5","schema_version":"1.0","event_id":"sha256:02ebe1b52f99fc8b00608f639a20ffcc0d75492a7f269e75c344bcdea49ecef5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:KXIJOL67E4WNHQ2R7U2KK2Z4AR","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Purity and Covariance Matrix","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"T. Golubeva, Yu. Golubev","submitted_at":"2013-12-20T22:00:54Z","abstract_excerpt":"Basing on the simplest single-mode field source, we investigate the role of the various covariance matrices for reconstructing the field state and describing its quantum statistical properties. In spite of the fact that the intracavity field is a single-mode field, we take into account the natural multimode structure arising in the field, when it leaves the cavity for the free-space propagation. We show how the purity of the field state can be calculated using the different covariance matrices."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1312.6160","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":"2026-05-18T03:04:05Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"TfitWGqv6bGPgFwthpPmrtzZaZaVTF9S1RUGiRZGi9TdtacqNXakLj9ZudNk49afNMd3BEsSak2p8Kxe//IVCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T14:15:51.689338Z"},"content_sha256":"9c582d671b3fd3648463d2df415fd7e8c0f103f44c6cbfa5fba5aa3d27893865","schema_version":"1.0","event_id":"sha256:9c582d671b3fd3648463d2df415fd7e8c0f103f44c6cbfa5fba5aa3d27893865"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/bundle.json","state_url":"https://pith.science/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/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":"2026-06-07T14:15:51Z","links":{"resolver":"https://pith.science/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR","bundle":"https://pith.science/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/bundle.json","state":"https://pith.science/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/state.json","well_known_bundle":"https://pith.science/.well-known/pith/KXIJOL67E4WNHQ2R7U2KK2Z4AR/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:KXIJOL67E4WNHQ2R7U2KK2Z4AR","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":"a23587027add0683eb3d531b36d4413bf68f42d9185613b58c02ebd71d1b223b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-12-20T22:00:54Z","title_canon_sha256":"45ca7da228fc9e56c20259423e65ebfb827769f5206dcba2da14a0ff456c5202"},"schema_version":"1.0","source":{"id":"1312.6160","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1312.6160","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"arxiv_version","alias_value":"1312.6160v1","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1312.6160","created_at":"2026-05-18T03:04:05Z"},{"alias_kind":"pith_short_12","alias_value":"KXIJOL67E4WN","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_16","alias_value":"KXIJOL67E4WNHQ2R","created_at":"2026-05-18T12:27:51Z"},{"alias_kind":"pith_short_8","alias_value":"KXIJOL67","created_at":"2026-05-18T12:27:51Z"}],"graph_snapshots":[{"event_id":"sha256:9c582d671b3fd3648463d2df415fd7e8c0f103f44c6cbfa5fba5aa3d27893865","target":"graph","created_at":"2026-05-18T03:04:05Z","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":"Basing on the simplest single-mode field source, we investigate the role of the various covariance matrices for reconstructing the field state and describing its quantum statistical properties. In spite of the fact that the intracavity field is a single-mode field, we take into account the natural multimode structure arising in the field, when it leaves the cavity for the free-space propagation. We show how the purity of the field state can be calculated using the different covariance matrices.","authors_text":"T. Golubeva, Yu. Golubev","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-12-20T22:00:54Z","title":"Purity and Covariance Matrix"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1312.6160","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":"sha256:02ebe1b52f99fc8b00608f639a20ffcc0d75492a7f269e75c344bcdea49ecef5","target":"record","created_at":"2026-05-18T03:04:05Z","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":"a23587027add0683eb3d531b36d4413bf68f42d9185613b58c02ebd71d1b223b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-12-20T22:00:54Z","title_canon_sha256":"45ca7da228fc9e56c20259423e65ebfb827769f5206dcba2da14a0ff456c5202"},"schema_version":"1.0","source":{"id":"1312.6160","kind":"arxiv","version":1}},"canonical_sha256":"55d0972fdf272cd3c351fd34a56b3c046fd6378dc14837f14401ab35fac3f5a2","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"55d0972fdf272cd3c351fd34a56b3c046fd6378dc14837f14401ab35fac3f5a2","first_computed_at":"2026-05-18T03:04:05.894578Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:04:05.894578Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"+uPRNiW9CyPLeQheINZumj5fy0EhpQTJbFH7jW+VUxOOHJIm7hFXc2e9XIYvrSuzZOjyoktvAsD+WFgYLQa3Aw==","signature_status":"signed_v1","signed_at":"2026-05-18T03:04:05.895270Z","signed_message":"canonical_sha256_bytes"},"source_id":"1312.6160","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:02ebe1b52f99fc8b00608f639a20ffcc0d75492a7f269e75c344bcdea49ecef5","sha256:9c582d671b3fd3648463d2df415fd7e8c0f103f44c6cbfa5fba5aa3d27893865"],"state_sha256":"62ee1995b8319b587d171d159a26fc7992b6883347967f6f54de158a14f4797f"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qDinyUWXaRlTvLGPBv0ahswms3ao4nyNceFPoyv0Uqfch+BClea2bMZNGJnffwjI6dO+Y9jtNFj8NqdizyuvBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-07T14:15:51.693244Z","bundle_sha256":"3e71419847f0b7b002095f962463730ffee2181421d3cc9b77ac9a5fad8a111d"}}