{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:UPSYACNIUA54SO5IPMF42NQNN7","short_pith_number":"pith:UPSYACNI","canonical_record":{"source":{"id":"1204.5294","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-24T08:14:22Z","cross_cats_sorted":["gr-qc"],"title_canon_sha256":"475e0b2e9f5ee9088540b4f06c158893d1c147d8740d5838a1b88d9223884e52","abstract_canon_sha256":"5e464420590ae2bbcd8ded4122bb69f0ce7fcad784da639705b090f31e051ef2"},"schema_version":"1.0"},"canonical_sha256":"a3e58009a8a03bc93ba87b0bcd360d6feea78babc819a1f3aa45bc4ce9ebbb89","source":{"kind":"arxiv","id":"1204.5294","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1204.5294","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"arxiv_version","alias_value":"1204.5294v1","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1204.5294","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"pith_short_12","alias_value":"UPSYACNIUA54","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_16","alias_value":"UPSYACNIUA54SO5I","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_8","alias_value":"UPSYACNI","created_at":"2026-05-18T12:27:23Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:UPSYACNIUA54SO5IPMF42NQNN7","target":"record","payload":{"canonical_record":{"source":{"id":"1204.5294","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-24T08:14:22Z","cross_cats_sorted":["gr-qc"],"title_canon_sha256":"475e0b2e9f5ee9088540b4f06c158893d1c147d8740d5838a1b88d9223884e52","abstract_canon_sha256":"5e464420590ae2bbcd8ded4122bb69f0ce7fcad784da639705b090f31e051ef2"},"schema_version":"1.0"},"canonical_sha256":"a3e58009a8a03bc93ba87b0bcd360d6feea78babc819a1f3aa45bc4ce9ebbb89","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:57:46.917314Z","signature_b64":"xNQSoLtbrfxgAsQxojIjvYcjl14/iVKu7Yj5ngUkPd7EQn4zwuCzO7pj0pOhDoxcI5M2stTIhzGAR+iLClhoDw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a3e58009a8a03bc93ba87b0bcd360d6feea78babc819a1f3aa45bc4ce9ebbb89","last_reissued_at":"2026-05-18T01:57:46.916617Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:57:46.916617Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1204.5294","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":"2026-05-18T01:57:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vg5LaXV10s9DD9vEmN5jCGl6+gv69y8uQJ5ABHEoF9ZZm4Fqd0LwIEurOStlUEDCCNeBo3cOte/fl6tqg79MAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-21T12:01:14.866853Z"},"content_sha256":"4dec1cf28e8ca478eb750df874a5b5b32c3cf779d8626511b97db01ef9d9b712","schema_version":"1.0","event_id":"sha256:4dec1cf28e8ca478eb750df874a5b5b32c3cf779d8626511b97db01ef9d9b712"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:UPSYACNIUA54SO5IPMF42NQNN7","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Accelerating f(T) gravity models constrained by recent cosmological data","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["gr-qc"],"primary_cat":"astro-ph.CO","authors_text":"Ninfa Radicella, Stefano Camera, Vincenzo F. Cardone","submitted_at":"2012-04-24T08:14:22Z","abstract_excerpt":"Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an effective torsion fluid whose equation of state depend on the f(T) function entering the modified gravity Lagrangian. We focus on two particular choices for f(T) which share the nice property to emulate a phantom divide crossing as suggested by some recent data. We check their viability contrasting the predicted background dynamics to the Hubble diagram as "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1204.5294","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":""},"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":"2026-05-18T01:57:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xMcQfyCzDskzG/vJda3gC9QD4F1rBsyWHsGxzMqe5nLfbD9l1pxKPVHV+vRV7Tk7vXfcXbVMh2D7BFEpomsLAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-21T12:01:14.867499Z"},"content_sha256":"66a3e4fc61990eff1fa3c80086808e08a646d27b6aec3a7aa0014674bdb272ba","schema_version":"1.0","event_id":"sha256:66a3e4fc61990eff1fa3c80086808e08a646d27b6aec3a7aa0014674bdb272ba"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UPSYACNIUA54SO5IPMF42NQNN7/bundle.json","state_url":"https://pith.science/pith/UPSYACNIUA54SO5IPMF42NQNN7/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UPSYACNIUA54SO5IPMF42NQNN7/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":"2026-05-21T12:01:14Z","links":{"resolver":"https://pith.science/pith/UPSYACNIUA54SO5IPMF42NQNN7","bundle":"https://pith.science/pith/UPSYACNIUA54SO5IPMF42NQNN7/bundle.json","state":"https://pith.science/pith/UPSYACNIUA54SO5IPMF42NQNN7/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UPSYACNIUA54SO5IPMF42NQNN7/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:UPSYACNIUA54SO5IPMF42NQNN7","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":"5e464420590ae2bbcd8ded4122bb69f0ce7fcad784da639705b090f31e051ef2","cross_cats_sorted":["gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-24T08:14:22Z","title_canon_sha256":"475e0b2e9f5ee9088540b4f06c158893d1c147d8740d5838a1b88d9223884e52"},"schema_version":"1.0","source":{"id":"1204.5294","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1204.5294","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"arxiv_version","alias_value":"1204.5294v1","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1204.5294","created_at":"2026-05-18T01:57:46Z"},{"alias_kind":"pith_short_12","alias_value":"UPSYACNIUA54","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_16","alias_value":"UPSYACNIUA54SO5I","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_8","alias_value":"UPSYACNI","created_at":"2026-05-18T12:27:23Z"}],"graph_snapshots":[{"event_id":"sha256:66a3e4fc61990eff1fa3c80086808e08a646d27b6aec3a7aa0014674bdb272ba","target":"graph","created_at":"2026-05-18T01:57:46Z","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":"Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an effective torsion fluid whose equation of state depend on the f(T) function entering the modified gravity Lagrangian. We focus on two particular choices for f(T) which share the nice property to emulate a phantom divide crossing as suggested by some recent data. We check their viability contrasting the predicted background dynamics to the Hubble diagram as ","authors_text":"Ninfa Radicella, Stefano Camera, Vincenzo F. Cardone","cross_cats":["gr-qc"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-24T08:14:22Z","title":"Accelerating f(T) gravity models constrained by recent cosmological data"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1204.5294","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":"sha256:4dec1cf28e8ca478eb750df874a5b5b32c3cf779d8626511b97db01ef9d9b712","target":"record","created_at":"2026-05-18T01:57:46Z","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":"5e464420590ae2bbcd8ded4122bb69f0ce7fcad784da639705b090f31e051ef2","cross_cats_sorted":["gr-qc"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-24T08:14:22Z","title_canon_sha256":"475e0b2e9f5ee9088540b4f06c158893d1c147d8740d5838a1b88d9223884e52"},"schema_version":"1.0","source":{"id":"1204.5294","kind":"arxiv","version":1}},"canonical_sha256":"a3e58009a8a03bc93ba87b0bcd360d6feea78babc819a1f3aa45bc4ce9ebbb89","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a3e58009a8a03bc93ba87b0bcd360d6feea78babc819a1f3aa45bc4ce9ebbb89","first_computed_at":"2026-05-18T01:57:46.916617Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:57:46.916617Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"xNQSoLtbrfxgAsQxojIjvYcjl14/iVKu7Yj5ngUkPd7EQn4zwuCzO7pj0pOhDoxcI5M2stTIhzGAR+iLClhoDw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:57:46.917314Z","signed_message":"canonical_sha256_bytes"},"source_id":"1204.5294","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4dec1cf28e8ca478eb750df874a5b5b32c3cf779d8626511b97db01ef9d9b712","sha256:66a3e4fc61990eff1fa3c80086808e08a646d27b6aec3a7aa0014674bdb272ba"],"state_sha256":"1a1fca82be818b0423e84fc7b05b0062515235c3ddfb7c5a0f48ab74766dc85a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1gVbElENpdTz9tc28x+MbLCxfutDl7/UHspF4NsqDPFXdavy3lxLdHEpUwjTBoWKOgkVFznyNaJhi1LfCg6ZCA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-21T12:01:14.869780Z","bundle_sha256":"1c82c5077632fab56540bdb4783fdc3c0ff2e3dbde786083c32df4c19183d004"}}