{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:B75NNRYWRQPE5H6WCJKRSHHUYI","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":"4a2f9e7b50e2795020138a3c9f710fc269bafe76c80832a9816f46d4f60186c3","cross_cats_sorted":["gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-03-21T17:49:02Z","title_canon_sha256":"1191bcdce8984a0d6b63578f1c42e25d9f9a7fdc14ac0b871f748bdd012b59d8"},"schema_version":"1.0","source":{"id":"1203.4790","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1203.4790","created_at":"2026-05-18T01:58:04Z"},{"alias_kind":"arxiv_version","alias_value":"1203.4790v2","created_at":"2026-05-18T01:58:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1203.4790","created_at":"2026-05-18T01:58:04Z"},{"alias_kind":"pith_short_12","alias_value":"B75NNRYWRQPE","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_16","alias_value":"B75NNRYWRQPE5H6W","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_8","alias_value":"B75NNRYW","created_at":"2026-05-18T12:26:58Z"}],"graph_snapshots":[{"event_id":"sha256:ed600611b176bd49d627732e2dece9958d8647048a3e2029cf1e789f88eb619c","target":"graph","created_at":"2026-05-18T01:58:04Z","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":"Increasingly accurate observations of the cosmic microwave background and the large scale distribution of galaxies necessitate the study of nonlinear perturbations of Friedmann-Lemaitre cosmologies, whose equations are notoriously complicated. In this paper we present a new derivation of the governing equations for second order perturbations within the framework of the metric-based approach that is minimal, as regards amount of calculation and length of expressions, and flexible, as regards choice of gauge and stress-energy tensor. Because of their generality and the simplicity of their struct","authors_text":"Claes Uggla, John Wainwright","cross_cats":["gr-qc"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-03-21T17:49:02Z","title":"A simplified structure for the second order cosmological perturbation equations"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1203.4790","kind":"arxiv","version":2},"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":"sha256:6623c4594dfbe4e7bcd240c101e4381e1b8d013403e832f709e7ed5e09f88691","target":"record","created_at":"2026-05-18T01:58:04Z","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":"4a2f9e7b50e2795020138a3c9f710fc269bafe76c80832a9816f46d4f60186c3","cross_cats_sorted":["gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-03-21T17:49:02Z","title_canon_sha256":"1191bcdce8984a0d6b63578f1c42e25d9f9a7fdc14ac0b871f748bdd012b59d8"},"schema_version":"1.0","source":{"id":"1203.4790","kind":"arxiv","version":2}},"canonical_sha256":"0ffad6c7168c1e4e9fd61255191cf4c22b1ed97dc73bd5a6bf7a4aea285b2f56","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0ffad6c7168c1e4e9fd61255191cf4c22b1ed97dc73bd5a6bf7a4aea285b2f56","first_computed_at":"2026-05-18T01:58:04.924064Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:58:04.924064Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"B24N6xG/pv4GjbGW3P1jHmwl5/4r5BiJ6H8avNTzwEYuqLBMI9dO5lOf4rmuYux6iFLV9LRdZImeq6v1bbyYBw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:58:04.924610Z","signed_message":"canonical_sha256_bytes"},"source_id":"1203.4790","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:6623c4594dfbe4e7bcd240c101e4381e1b8d013403e832f709e7ed5e09f88691","sha256:ed600611b176bd49d627732e2dece9958d8647048a3e2029cf1e789f88eb619c"],"state_sha256":"e8b1253e42f684575c79fde106643b90cafffcd28587eb1749b6efa39cad14f2"}