{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:WGOUUNMYZDPSJEZKP4GYTCSTJU","short_pith_number":"pith:WGOUUNMY","canonical_record":{"source":{"id":"2104.05890","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2021-04-13T01:45:43Z","cross_cats_sorted":["physics.optics"],"title_canon_sha256":"52b473ba5dc08283ee8afd083fd7e60a93c75e4221e3e2223c0d14827b852a09","abstract_canon_sha256":"b9fb062add8939196964826d8790fec61d74e11cd8fece5ed3ede1f685415991"},"schema_version":"1.0"},"canonical_sha256":"b19d4a3598c8df24932a7f0d898a534d25498c6b59e9451729ba7b3984293068","source":{"kind":"arxiv","id":"2104.05890","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2104.05890","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"arxiv_version","alias_value":"2104.05890v1","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2104.05890","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_12","alias_value":"WGOUUNMYZDPS","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_16","alias_value":"WGOUUNMYZDPSJEZK","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_8","alias_value":"WGOUUNMY","created_at":"2026-07-05T02:31:26Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:WGOUUNMYZDPSJEZKP4GYTCSTJU","target":"record","payload":{"canonical_record":{"source":{"id":"2104.05890","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2021-04-13T01:45:43Z","cross_cats_sorted":["physics.optics"],"title_canon_sha256":"52b473ba5dc08283ee8afd083fd7e60a93c75e4221e3e2223c0d14827b852a09","abstract_canon_sha256":"b9fb062add8939196964826d8790fec61d74e11cd8fece5ed3ede1f685415991"},"schema_version":"1.0"},"canonical_sha256":"b19d4a3598c8df24932a7f0d898a534d25498c6b59e9451729ba7b3984293068","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T02:31:26.355683Z","signature_b64":"cfIrRaTaaS6uZXPBpusnUOzfqPlv2j8gw0eDNxqA4nLY2RblGtmaCMWowLrNTLDHxphnE5hnAgLCyLIw//pNDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b19d4a3598c8df24932a7f0d898a534d25498c6b59e9451729ba7b3984293068","last_reissued_at":"2026-07-05T02:31:26.355098Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T02:31:26.355098Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2104.05890","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":"2026-07-05T02:31:26Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MmuGb/gN9QHPTV97+6vn43RsEabvuqd32lqHmejIomLKSTvpblu1HCmqi1cBZ/FSMo5wE1T1ofbFYUY3G3vaCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T09:37:23.789225Z"},"content_sha256":"a4cf917006d9e80b3d3534c64967d83c51a9733078c1e6658cca56a880fc158d","schema_version":"1.0","event_id":"sha256:a4cf917006d9e80b3d3534c64967d83c51a9733078c1e6658cca56a880fc158d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:WGOUUNMYZDPSJEZKP4GYTCSTJU","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Physics-oriented learning of nonlinear Schr\\\"odinger equation: optical fiber loss and dispersion profile identification","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.optics"],"primary_cat":"eess.SP","authors_text":"Etsushi Yamazaki, Hideki Nishizawa, Masanori Nakamura, Shuto Yamamoto, Takeo Sasai, Yoshiaki Kisaka","submitted_at":"2021-04-13T01:45:43Z","abstract_excerpt":"In optical fiber communication, system identification (SI) for the nonlinear Schr\\\"odinger equation (NLSE) has long been studied mainly for fiber nonlinearity compensation (NLC). One recent line of inquiry to combine a behavioral-model approach like digital backpropagation (DBP) and a data-driven approach like neural network (NN). These works are aimed for more NLC gain; however, by directing our attention to the learned parameters in such a SI process, system status information, i.e., optical fiber parameters, will possibly be extracted. Here, we show that the model-based optimization and int"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2104.05890","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/2104.05890/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":"2026-07-05T02:31:26Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"U2lfEzB8zjUkxfrFNyJAzE0Dy3BgbKudrzX+UDEa7i5B1y4od7DFctKJM4+IH+yLp3sZrZmmhPto5R9mi/mSAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T09:37:23.789609Z"},"content_sha256":"3eda60be33a131957e95d7c4f6d233497e49154bc72235a8cc304d8771c184b1","schema_version":"1.0","event_id":"sha256:3eda60be33a131957e95d7c4f6d233497e49154bc72235a8cc304d8771c184b1"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/bundle.json","state_url":"https://pith.science/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/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":"2026-07-07T09:37:23Z","links":{"resolver":"https://pith.science/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU","bundle":"https://pith.science/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/bundle.json","state":"https://pith.science/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/state.json","well_known_bundle":"https://pith.science/.well-known/pith/WGOUUNMYZDPSJEZKP4GYTCSTJU/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:WGOUUNMYZDPSJEZKP4GYTCSTJU","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":"b9fb062add8939196964826d8790fec61d74e11cd8fece5ed3ede1f685415991","cross_cats_sorted":["physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2021-04-13T01:45:43Z","title_canon_sha256":"52b473ba5dc08283ee8afd083fd7e60a93c75e4221e3e2223c0d14827b852a09"},"schema_version":"1.0","source":{"id":"2104.05890","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2104.05890","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"arxiv_version","alias_value":"2104.05890v1","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2104.05890","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_12","alias_value":"WGOUUNMYZDPS","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_16","alias_value":"WGOUUNMYZDPSJEZK","created_at":"2026-07-05T02:31:26Z"},{"alias_kind":"pith_short_8","alias_value":"WGOUUNMY","created_at":"2026-07-05T02:31:26Z"}],"graph_snapshots":[{"event_id":"sha256:3eda60be33a131957e95d7c4f6d233497e49154bc72235a8cc304d8771c184b1","target":"graph","created_at":"2026-07-05T02:31:26Z","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/2104.05890/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In optical fiber communication, system identification (SI) for the nonlinear Schr\\\"odinger equation (NLSE) has long been studied mainly for fiber nonlinearity compensation (NLC). One recent line of inquiry to combine a behavioral-model approach like digital backpropagation (DBP) and a data-driven approach like neural network (NN). These works are aimed for more NLC gain; however, by directing our attention to the learned parameters in such a SI process, system status information, i.e., optical fiber parameters, will possibly be extracted. Here, we show that the model-based optimization and int","authors_text":"Etsushi Yamazaki, Hideki Nishizawa, Masanori Nakamura, Shuto Yamamoto, Takeo Sasai, Yoshiaki Kisaka","cross_cats":["physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2021-04-13T01:45:43Z","title":"Physics-oriented learning of nonlinear Schr\\\"odinger equation: optical fiber loss and dispersion profile identification"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2104.05890","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:a4cf917006d9e80b3d3534c64967d83c51a9733078c1e6658cca56a880fc158d","target":"record","created_at":"2026-07-05T02:31:26Z","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":"b9fb062add8939196964826d8790fec61d74e11cd8fece5ed3ede1f685415991","cross_cats_sorted":["physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2021-04-13T01:45:43Z","title_canon_sha256":"52b473ba5dc08283ee8afd083fd7e60a93c75e4221e3e2223c0d14827b852a09"},"schema_version":"1.0","source":{"id":"2104.05890","kind":"arxiv","version":1}},"canonical_sha256":"b19d4a3598c8df24932a7f0d898a534d25498c6b59e9451729ba7b3984293068","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b19d4a3598c8df24932a7f0d898a534d25498c6b59e9451729ba7b3984293068","first_computed_at":"2026-07-05T02:31:26.355098Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:31:26.355098Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"cfIrRaTaaS6uZXPBpusnUOzfqPlv2j8gw0eDNxqA4nLY2RblGtmaCMWowLrNTLDHxphnE5hnAgLCyLIw//pNDA==","signature_status":"signed_v1","signed_at":"2026-07-05T02:31:26.355683Z","signed_message":"canonical_sha256_bytes"},"source_id":"2104.05890","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:a4cf917006d9e80b3d3534c64967d83c51a9733078c1e6658cca56a880fc158d","sha256:3eda60be33a131957e95d7c4f6d233497e49154bc72235a8cc304d8771c184b1"],"state_sha256":"e29713d12696f702323213c32174d18096533b798542d21aadd3428ccc6777b9"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"2Yc+UMMgGGrAGoivvD/oX2dw/Bz7L7Xw3sQwTZA0zcv1Md7NIde7xA46ZsFkxuOqRBr/++csggCPbAVoCwZmDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-07T09:37:23.791584Z","bundle_sha256":"d6b08d7078a35a2d481a89fbec9bc26ef0339384546bde28f0464607a027446c"}}