{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2023:V7YVX2TF2G6IUP3LR64HAL5VOH","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":"ead55f39c797e3cd54b6c4189e5864dc4e9168e52072aee9f2e612367c857dae","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2023-05-02T06:27:54Z","title_canon_sha256":"8c6ffe5852e8856ee695f6d1cb9b5f98b69c1c0a1837b3dd1c06e7c559e2456a"},"schema_version":"1.0","source":{"id":"2305.01223","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2305.01223","created_at":"2026-07-05T06:13:39Z"},{"alias_kind":"arxiv_version","alias_value":"2305.01223v2","created_at":"2026-07-05T06:13:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2305.01223","created_at":"2026-07-05T06:13:39Z"},{"alias_kind":"pith_short_12","alias_value":"V7YVX2TF2G6I","created_at":"2026-07-05T06:13:39Z"},{"alias_kind":"pith_short_16","alias_value":"V7YVX2TF2G6IUP3L","created_at":"2026-07-05T06:13:39Z"},{"alias_kind":"pith_short_8","alias_value":"V7YVX2TF","created_at":"2026-07-05T06:13:39Z"}],"graph_snapshots":[{"event_id":"sha256:02eaa9372de2c5dc8d0b92fa495b318cb08236a275267facf91c91d67bab8208","target":"graph","created_at":"2026-07-05T06:13:39Z","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/2305.01223/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"The possibility of obtaining symbolic expressions for cosmic backreaction is explored through a case study of so-called 2-region models. By using the publicly available symbolic regression algorithm AI Feynman, it is shown that the kinematical backreaction from a single 2-region model can be well described as a function of the mean redshift (or, equivalently, the volume averaged scale factor). A single expression depending on the redshift/scale factor as well as a model parameter, $f$, that can accurately describe the backreaction for a significant range of models is naturally more complicated","authors_text":"S. M. Koksbang","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2023-05-02T06:27:54Z","title":"Cosmic backreaction and the mean redshift drift from symbolic regression"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2305.01223","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:b832a1a673cd4975cff00c1e992a5f88b9cf8dbe3af37e80c2d902b4487ff5df","target":"record","created_at":"2026-07-05T06:13:39Z","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":"ead55f39c797e3cd54b6c4189e5864dc4e9168e52072aee9f2e612367c857dae","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2023-05-02T06:27:54Z","title_canon_sha256":"8c6ffe5852e8856ee695f6d1cb9b5f98b69c1c0a1837b3dd1c06e7c559e2456a"},"schema_version":"1.0","source":{"id":"2305.01223","kind":"arxiv","version":2}},"canonical_sha256":"aff15bea65d1bc8a3f6b8fb8702fb571c8c5099a056b79a5be02642059fba074","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"aff15bea65d1bc8a3f6b8fb8702fb571c8c5099a056b79a5be02642059fba074","first_computed_at":"2026-07-05T06:13:39.075899Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T06:13:39.075899Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OcngsudIkSn4gKgrWgssfGRnlzPFWfLpID0pBiALoJoTFHcoFdtVumIcJQ8ukmdwHWitr5B1Rw/quC/Q31/dCw==","signature_status":"signed_v1","signed_at":"2026-07-05T06:13:39.076409Z","signed_message":"canonical_sha256_bytes"},"source_id":"2305.01223","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b832a1a673cd4975cff00c1e992a5f88b9cf8dbe3af37e80c2d902b4487ff5df","sha256:02eaa9372de2c5dc8d0b92fa495b318cb08236a275267facf91c91d67bab8208"],"state_sha256":"2933e971ddc19a5e6f2b39e0a3a70becfa1b1ad041cd40e92a5539e00bfcad43"}