{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2010:4TBGSTNRIDKNRULS6WWVKQOLDG","short_pith_number":"pith:4TBGSTNR","canonical_record":{"source":{"id":"1004.2245","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2010-04-13T18:45:46Z","cross_cats_sorted":[],"title_canon_sha256":"d525e52ad9b598dec3d813f2591b9b16d7b7ede20953cdc3ffd6da6a14ca6355","abstract_canon_sha256":"9d185e4501d9519bcb92d7bec2bf6bf22aa5d4b8df6c50f59619fd6dbc786752"},"schema_version":"1.0"},"canonical_sha256":"e4c2694db140d4d8d172f5ad5541cb19a98bc4a4fb28495d0b7493fda11f5d1b","source":{"kind":"arxiv","id":"1004.2245","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1004.2245","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"arxiv_version","alias_value":"1004.2245v1","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1004.2245","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"pith_short_12","alias_value":"4TBGSTNRIDKN","created_at":"2026-05-18T12:26:04Z"},{"alias_kind":"pith_short_16","alias_value":"4TBGSTNRIDKNRULS","created_at":"2026-05-18T12:26:04Z"},{"alias_kind":"pith_short_8","alias_value":"4TBGSTNR","created_at":"2026-05-18T12:26:04Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2010:4TBGSTNRIDKNRULS6WWVKQOLDG","target":"record","payload":{"canonical_record":{"source":{"id":"1004.2245","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2010-04-13T18:45:46Z","cross_cats_sorted":[],"title_canon_sha256":"d525e52ad9b598dec3d813f2591b9b16d7b7ede20953cdc3ffd6da6a14ca6355","abstract_canon_sha256":"9d185e4501d9519bcb92d7bec2bf6bf22aa5d4b8df6c50f59619fd6dbc786752"},"schema_version":"1.0"},"canonical_sha256":"e4c2694db140d4d8d172f5ad5541cb19a98bc4a4fb28495d0b7493fda11f5d1b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:35:48.952544Z","signature_b64":"rYjLaMGRXy6r2Ft19vHGBmz2XyHcD0FsfGuooXKDQL3rRHbOJXUDjSZ+mlEqTPWSq36eLj+VhiKIaJuN3SLFAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e4c2694db140d4d8d172f5ad5541cb19a98bc4a4fb28495d0b7493fda11f5d1b","last_reissued_at":"2026-05-18T04:35:48.952118Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:35:48.952118Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1004.2245","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":"2026-05-18T04:35:48Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"C/EcR8q4KZKgFl5dVFt7FsiM0Z10SWXBKC9fJ2xIwoGGv/v/LpCZtM+Jmgb2fZJbph/jdwTXuOpY0L/XRROYDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T18:42:01.416101Z"},"content_sha256":"9b0087a488e014ca48b281dc332c7c5094e91734b83d9cf0cd149c15cff6ed2b","schema_version":"1.0","event_id":"sha256:9b0087a488e014ca48b281dc332c7c5094e91734b83d9cf0cd149c15cff6ed2b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2010:4TBGSTNRIDKNRULS6WWVKQOLDG","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Linear-optical processing cannot increase photon efficiency","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"A. I. Lvovsky, D. W. Berry","submitted_at":"2010-04-13T18:45:46Z","abstract_excerpt":"We answer the question whether linear-optical processing of the states produced by one or multiple imperfect single-photon sources can improve the single-photon fidelity.  This processing can include arbitrary interferometers, coherent states, feedforward, and conditioning on results of detections.  We show that without introducing multiphoton components, the single-photon fraction in any of the single-mode states resulting from such processing cannot be made to exceed the efficiency of the best available photon source.  If multiphoton components are allowed, the single-photon fidelity cannot "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1004.2245","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":"2026-05-18T04:35:48Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xz1DkbF/CEntA4YNygHa5RvxMyFvyfx3b1KHgneGJKmW+pKyJsxuyal7nX3VmzU48HGJ0zGgjrj4Lucc9podBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T18:42:01.416781Z"},"content_sha256":"a4f636be7115672afe3ab0ba31ca7f6950c962f19dc001f7903267f3fd040eda","schema_version":"1.0","event_id":"sha256:a4f636be7115672afe3ab0ba31ca7f6950c962f19dc001f7903267f3fd040eda"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/bundle.json","state_url":"https://pith.science/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/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":"2026-05-27T18:42:01Z","links":{"resolver":"https://pith.science/pith/4TBGSTNRIDKNRULS6WWVKQOLDG","bundle":"https://pith.science/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/bundle.json","state":"https://pith.science/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4TBGSTNRIDKNRULS6WWVKQOLDG/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2010:4TBGSTNRIDKNRULS6WWVKQOLDG","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":"9d185e4501d9519bcb92d7bec2bf6bf22aa5d4b8df6c50f59619fd6dbc786752","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2010-04-13T18:45:46Z","title_canon_sha256":"d525e52ad9b598dec3d813f2591b9b16d7b7ede20953cdc3ffd6da6a14ca6355"},"schema_version":"1.0","source":{"id":"1004.2245","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1004.2245","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"arxiv_version","alias_value":"1004.2245v1","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1004.2245","created_at":"2026-05-18T04:35:48Z"},{"alias_kind":"pith_short_12","alias_value":"4TBGSTNRIDKN","created_at":"2026-05-18T12:26:04Z"},{"alias_kind":"pith_short_16","alias_value":"4TBGSTNRIDKNRULS","created_at":"2026-05-18T12:26:04Z"},{"alias_kind":"pith_short_8","alias_value":"4TBGSTNR","created_at":"2026-05-18T12:26:04Z"}],"graph_snapshots":[{"event_id":"sha256:a4f636be7115672afe3ab0ba31ca7f6950c962f19dc001f7903267f3fd040eda","target":"graph","created_at":"2026-05-18T04:35:48Z","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 answer the question whether linear-optical processing of the states produced by one or multiple imperfect single-photon sources can improve the single-photon fidelity.  This processing can include arbitrary interferometers, coherent states, feedforward, and conditioning on results of detections.  We show that without introducing multiphoton components, the single-photon fraction in any of the single-mode states resulting from such processing cannot be made to exceed the efficiency of the best available photon source.  If multiphoton components are allowed, the single-photon fidelity cannot ","authors_text":"A. I. Lvovsky, D. W. Berry","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2010-04-13T18:45:46Z","title":"Linear-optical processing cannot increase photon efficiency"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1004.2245","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":"sha256:9b0087a488e014ca48b281dc332c7c5094e91734b83d9cf0cd149c15cff6ed2b","target":"record","created_at":"2026-05-18T04:35:48Z","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":"9d185e4501d9519bcb92d7bec2bf6bf22aa5d4b8df6c50f59619fd6dbc786752","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2010-04-13T18:45:46Z","title_canon_sha256":"d525e52ad9b598dec3d813f2591b9b16d7b7ede20953cdc3ffd6da6a14ca6355"},"schema_version":"1.0","source":{"id":"1004.2245","kind":"arxiv","version":1}},"canonical_sha256":"e4c2694db140d4d8d172f5ad5541cb19a98bc4a4fb28495d0b7493fda11f5d1b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e4c2694db140d4d8d172f5ad5541cb19a98bc4a4fb28495d0b7493fda11f5d1b","first_computed_at":"2026-05-18T04:35:48.952118Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:35:48.952118Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"rYjLaMGRXy6r2Ft19vHGBmz2XyHcD0FsfGuooXKDQL3rRHbOJXUDjSZ+mlEqTPWSq36eLj+VhiKIaJuN3SLFAw==","signature_status":"signed_v1","signed_at":"2026-05-18T04:35:48.952544Z","signed_message":"canonical_sha256_bytes"},"source_id":"1004.2245","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:9b0087a488e014ca48b281dc332c7c5094e91734b83d9cf0cd149c15cff6ed2b","sha256:a4f636be7115672afe3ab0ba31ca7f6950c962f19dc001f7903267f3fd040eda"],"state_sha256":"82568ea39ec74aa1e6da72ff8f6eaca7778ce14d0996d18af7a85da4d6c83162"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"fGHzAYZPLWzOWQqUc+WHQBrIPvPHw4HBGxDQtXGOu3IYMPRMc9yrS8EdkX5o8kyrlfCarV72mKbO+dncYqe/BQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-27T18:42:01.420208Z","bundle_sha256":"c7bfa215e47b6ef61917f7bc188b29f9552dcfa266de3825aff688c33ccc6d43"}}