{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:C7QNYXRAHBU4EK2QJ5D6MMMQFK","short_pith_number":"pith:C7QNYXRA","canonical_record":{"source":{"id":"2109.09178","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2021-09-19T17:40:24Z","cross_cats_sorted":[],"title_canon_sha256":"301ff28e1b173663a8c812a19aba6d1ee7121ecb36a27491d61cd2e8fe371602","abstract_canon_sha256":"4d77c05f87ae1f05d4e3f64a296239f6b31e5929c0eca020f9c1e35284f2d02e"},"schema_version":"1.0"},"canonical_sha256":"17e0dc5e203869c22b504f47e631902a8a01e43f6f15c8ec96fa46a9a4c125e5","source":{"kind":"arxiv","id":"2109.09178","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2109.09178","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"arxiv_version","alias_value":"2109.09178v1","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2109.09178","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_12","alias_value":"C7QNYXRAHBU4","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_16","alias_value":"C7QNYXRAHBU4EK2Q","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_8","alias_value":"C7QNYXRA","created_at":"2026-07-05T03:15:42Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:C7QNYXRAHBU4EK2QJ5D6MMMQFK","target":"record","payload":{"canonical_record":{"source":{"id":"2109.09178","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2021-09-19T17:40:24Z","cross_cats_sorted":[],"title_canon_sha256":"301ff28e1b173663a8c812a19aba6d1ee7121ecb36a27491d61cd2e8fe371602","abstract_canon_sha256":"4d77c05f87ae1f05d4e3f64a296239f6b31e5929c0eca020f9c1e35284f2d02e"},"schema_version":"1.0"},"canonical_sha256":"17e0dc5e203869c22b504f47e631902a8a01e43f6f15c8ec96fa46a9a4c125e5","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:15:42.430771Z","signature_b64":"elAJJFpM5xfGNJPAtzJhVmo63NL//4ZpwwEs9c0z8RqyU8thKIg2E+ujAkgauQMAZKpzwRpqF592r1sp0ytWDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"17e0dc5e203869c22b504f47e631902a8a01e43f6f15c8ec96fa46a9a4c125e5","last_reissued_at":"2026-07-05T03:15:42.430411Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:15:42.430411Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2109.09178","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":"2026-07-05T03:15:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nzvz+A6zgYPE5hy8QF0250OxPbL4eqy0TXgaGOFS5shc3bzVGzAixoeTDrfTKBJqOr16tmtwgeUt8kpeht2cAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-01T05:38:56.123372Z"},"content_sha256":"4da411b2a2fac00a01787515a47f524391eed262ac2438c0601d1929b50ba928","schema_version":"1.0","event_id":"sha256:4da411b2a2fac00a01787515a47f524391eed262ac2438c0601d1929b50ba928"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:C7QNYXRAHBU4EK2QJ5D6MMMQFK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Distributed Quantum Sensing with Squeezed-Vacuum Light in a Configurable Network of Mach-Zehnder Interferometers","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Augusto Smerzi, Luca Pezz\\`e, Marco Malitesta","submitted_at":"2021-09-19T17:40:24Z","abstract_excerpt":"We study a sensor network of distributed Mach-Zehnder interferometers (MZIs) for the parallel (simultaneous) estimation of an arbitrary number $d \\geq 1$ of phase shifts. The scheme uses a squeezed-vacuum state that is split between $d$ modes by a quantum circuit (QC). Each output mode of the QC is the input of one of $d$ MZIs, the other input of each MZI being a coherent state. In particular, ${\\it i}$) we identify the optimal configuration of the sensor network that allows the estimation of any linear combination of the $d$ phases with maximal sensitivity. The protocol overcomes the shot-noi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2109.09178","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2109.09178/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T03:15:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nnb6IkhWG9qVdP0X4r/VhQJhbLtxkXiM6fdJZ5T2+oYedV8JZB6290IsSKJTbnMEW+PdiH8pSl5pY+CRL29EDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-01T05:38:56.124169Z"},"content_sha256":"1f4e17094a525a3b418331ae9c5ba2e9c93646b8b4af59471b86a0517a042d0e","schema_version":"1.0","event_id":"sha256:1f4e17094a525a3b418331ae9c5ba2e9c93646b8b4af59471b86a0517a042d0e"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/bundle.json","state_url":"https://pith.science/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/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":"2026-08-01T05:38:56Z","links":{"resolver":"https://pith.science/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK","bundle":"https://pith.science/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/bundle.json","state":"https://pith.science/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/C7QNYXRAHBU4EK2QJ5D6MMMQFK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:C7QNYXRAHBU4EK2QJ5D6MMMQFK","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":"4d77c05f87ae1f05d4e3f64a296239f6b31e5929c0eca020f9c1e35284f2d02e","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2021-09-19T17:40:24Z","title_canon_sha256":"301ff28e1b173663a8c812a19aba6d1ee7121ecb36a27491d61cd2e8fe371602"},"schema_version":"1.0","source":{"id":"2109.09178","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2109.09178","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"arxiv_version","alias_value":"2109.09178v1","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2109.09178","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_12","alias_value":"C7QNYXRAHBU4","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_16","alias_value":"C7QNYXRAHBU4EK2Q","created_at":"2026-07-05T03:15:42Z"},{"alias_kind":"pith_short_8","alias_value":"C7QNYXRA","created_at":"2026-07-05T03:15:42Z"}],"graph_snapshots":[{"event_id":"sha256:1f4e17094a525a3b418331ae9c5ba2e9c93646b8b4af59471b86a0517a042d0e","target":"graph","created_at":"2026-07-05T03:15:42Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2109.09178/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We study a sensor network of distributed Mach-Zehnder interferometers (MZIs) for the parallel (simultaneous) estimation of an arbitrary number $d \\geq 1$ of phase shifts. The scheme uses a squeezed-vacuum state that is split between $d$ modes by a quantum circuit (QC). Each output mode of the QC is the input of one of $d$ MZIs, the other input of each MZI being a coherent state. In particular, ${\\it i}$) we identify the optimal configuration of the sensor network that allows the estimation of any linear combination of the $d$ phases with maximal sensitivity. The protocol overcomes the shot-noi","authors_text":"Augusto Smerzi, Luca Pezz\\`e, Marco Malitesta","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2021-09-19T17:40:24Z","title":"Distributed Quantum Sensing with Squeezed-Vacuum Light in a Configurable Network of Mach-Zehnder Interferometers"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2109.09178","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":"sha256:4da411b2a2fac00a01787515a47f524391eed262ac2438c0601d1929b50ba928","target":"record","created_at":"2026-07-05T03:15:42Z","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":"4d77c05f87ae1f05d4e3f64a296239f6b31e5929c0eca020f9c1e35284f2d02e","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2021-09-19T17:40:24Z","title_canon_sha256":"301ff28e1b173663a8c812a19aba6d1ee7121ecb36a27491d61cd2e8fe371602"},"schema_version":"1.0","source":{"id":"2109.09178","kind":"arxiv","version":1}},"canonical_sha256":"17e0dc5e203869c22b504f47e631902a8a01e43f6f15c8ec96fa46a9a4c125e5","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"17e0dc5e203869c22b504f47e631902a8a01e43f6f15c8ec96fa46a9a4c125e5","first_computed_at":"2026-07-05T03:15:42.430411Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T03:15:42.430411Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"elAJJFpM5xfGNJPAtzJhVmo63NL//4ZpwwEs9c0z8RqyU8thKIg2E+ujAkgauQMAZKpzwRpqF592r1sp0ytWDA==","signature_status":"signed_v1","signed_at":"2026-07-05T03:15:42.430771Z","signed_message":"canonical_sha256_bytes"},"source_id":"2109.09178","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4da411b2a2fac00a01787515a47f524391eed262ac2438c0601d1929b50ba928","sha256:1f4e17094a525a3b418331ae9c5ba2e9c93646b8b4af59471b86a0517a042d0e"],"state_sha256":"0b17cee281155f42e9cd2f001649f3641bf0a1e59a8b4410df240a47bceaa158"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"EScy0WBp8TW8VP/q0JK0Z+eScJee/6t7HeJW6T34VZfNVzbZiVjrq4/wiByxKKtXRdc4CYwd5kPUSl0soTU8Bw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-01T05:38:56.130043Z","bundle_sha256":"347a1357172413d7b0ee61c56b889c9b3f410749aef10b834d2234d8c761c423"}}