{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2002:IBMEOKFNNRG2UQPL4UI537XJTT","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":"b0f914f431458dd63fb0285223402419c24cfd031c033cb14d2d7c609dae8823","cross_cats_sorted":[],"license":"","primary_cat":"gr-qc","submitted_at":"2002-04-05T23:15:37Z","title_canon_sha256":"a6da79a801cf002098415a4e90d110f76e3c349785b24370fee11bc342b49940"},"schema_version":"1.0","source":{"id":"gr-qc/0204028","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"gr-qc/0204028","created_at":"2026-07-04T16:33:43Z"},{"alias_kind":"arxiv_version","alias_value":"gr-qc/0204028v1","created_at":"2026-07-04T16:33:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.gr-qc/0204028","created_at":"2026-07-04T16:33:43Z"},{"alias_kind":"pith_short_12","alias_value":"IBMEOKFNNRG2","created_at":"2026-07-04T16:33:43Z"},{"alias_kind":"pith_short_16","alias_value":"IBMEOKFNNRG2UQPL","created_at":"2026-07-04T16:33:43Z"},{"alias_kind":"pith_short_8","alias_value":"IBMEOKFN","created_at":"2026-07-04T16:33:43Z"}],"graph_snapshots":[{"event_id":"sha256:b22141151acd28a8792667e36e88952dc8752fc0a45ee873f82bab130fbc6de5","target":"graph","created_at":"2026-07-04T16:33:43Z","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/gr-qc/0204028/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We study the wave propagation in nonlinear electrodynamical models. Particular attention is paid to the derivation and the analysis of the Fresnel equation for the wave covectors. For the class of general nonlinear Lagrangian models, we demonstrate how the originally quartic Fresnel equation factorizes, yielding the generic birefringence effect. We show that the closure of the effective constitutive (or jump) tensor is necessary and sufficient for the absence of birefringence, i.e., for the existence of a unique light cone structure. As another application of the Fresnel approach, we analyze t","authors_text":"Guillermo F. Rubilar, Yuri N. Obukhov","cross_cats":[],"headline":"","license":"","primary_cat":"gr-qc","submitted_at":"2002-04-05T23:15:37Z","title":"Fresnel analysis of the wave propagation in nonlinear electrodynamics"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"gr-qc/0204028","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":"sha256:7951bce628000cfe20480ce742f3713be9f9e383e343a0f6712707e757c93b99","target":"record","created_at":"2026-07-04T16:33:43Z","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":"b0f914f431458dd63fb0285223402419c24cfd031c033cb14d2d7c609dae8823","cross_cats_sorted":[],"license":"","primary_cat":"gr-qc","submitted_at":"2002-04-05T23:15:37Z","title_canon_sha256":"a6da79a801cf002098415a4e90d110f76e3c349785b24370fee11bc342b49940"},"schema_version":"1.0","source":{"id":"gr-qc/0204028","kind":"arxiv","version":1}},"canonical_sha256":"40584728ad6c4daa41ebe511ddfee99ce435200feb93dd253af6a28c921cb43b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"40584728ad6c4daa41ebe511ddfee99ce435200feb93dd253af6a28c921cb43b","first_computed_at":"2026-07-04T16:33:43.044004Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:33:43.044004Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"w/sykbD2EVVY5Y6J0oCKMidQb0RMmCLgMYNsy7Sl2clPnyA4z3jf6ynwr5CZ7B8pWXfA95PifG1U0b2s1aTKCA==","signature_status":"signed_v1","signed_at":"2026-07-04T16:33:43.044357Z","signed_message":"canonical_sha256_bytes"},"source_id":"gr-qc/0204028","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:7951bce628000cfe20480ce742f3713be9f9e383e343a0f6712707e757c93b99","sha256:b22141151acd28a8792667e36e88952dc8752fc0a45ee873f82bab130fbc6de5"],"state_sha256":"40699c09e0ef25d103b672b33823642016b44ec3373b85d4849d33d3f4cbafb4"}