{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:7M7ME3KNLYNGPKARMOBJMY75MH","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":"2688182d4df060b6728f72ff50e5465feee61bcd0fe5e4d52c6b0e71e4946bd4","cross_cats_sorted":["gr-qc","hep-th"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-09-19T08:16:03Z","title_canon_sha256":"ad68d1b48dd229a4d4c1e8ef662365ac006310fc48932d308855938c4a062cc7"},"schema_version":"1.0","source":{"id":"1909.08847","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1909.08847","created_at":"2026-07-05T00:43:37Z"},{"alias_kind":"arxiv_version","alias_value":"1909.08847v2","created_at":"2026-07-05T00:43:37Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1909.08847","created_at":"2026-07-05T00:43:37Z"},{"alias_kind":"pith_short_12","alias_value":"7M7ME3KNLYNG","created_at":"2026-07-05T00:43:37Z"},{"alias_kind":"pith_short_16","alias_value":"7M7ME3KNLYNGPKAR","created_at":"2026-07-05T00:43:37Z"},{"alias_kind":"pith_short_8","alias_value":"7M7ME3KN","created_at":"2026-07-05T00:43:37Z"}],"graph_snapshots":[{"event_id":"sha256:cfa3f8f7a864f9095901947ee8c5a946179626ce118f7451e16891251d615b29","target":"graph","created_at":"2026-07-05T00:43:37Z","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/1909.08847/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Within the framework of $f(R)=R+\\alpha R^2$ gravity, we study realistic models of neutron stars, using equations of state compatible with the LIGO constraints. i.e. APR4, MPA1, SLy, and WW1. By numerically solving modified Tolman-Oppenheimer-Volkoff equations, we investigate the Mass--Radius relation in both metric and torsional $f(R)=R+\\alpha R^2$ gravity models. In particular, we observe that torsion effects decrease the compactness and total mass of neutron star with respect to the General Relativity predictions, therefore mimicking the effects of a repulsive massive field. The opposite occ","authors_text":"Pasquale Feola, Roberto Cianci, Salvatore Capozziello, Stefano Vignolo, Xisco Jimenez Forteza","cross_cats":["gr-qc","hep-th"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-09-19T08:16:03Z","title":"The mass-radius relation for neutron stars in $f(R)=R+\\alpha R^2$ gravity: a comparison between purely metric and torsion formulations"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1909.08847","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:ee3eee5ac0f72e2be7cb5fd93f12191ce15145bfd68f04f7abfe902f74a0e4d6","target":"record","created_at":"2026-07-05T00:43:37Z","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":"2688182d4df060b6728f72ff50e5465feee61bcd0fe5e4d52c6b0e71e4946bd4","cross_cats_sorted":["gr-qc","hep-th"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-09-19T08:16:03Z","title_canon_sha256":"ad68d1b48dd229a4d4c1e8ef662365ac006310fc48932d308855938c4a062cc7"},"schema_version":"1.0","source":{"id":"1909.08847","kind":"arxiv","version":2}},"canonical_sha256":"fb3ec26d4d5e1a67a81163829663fd61e3c2f65b51d54e7cf1e8f2edf4860352","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fb3ec26d4d5e1a67a81163829663fd61e3c2f65b51d54e7cf1e8f2edf4860352","first_computed_at":"2026-07-05T00:43:37.349889Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:43:37.349889Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"vlzW40i1SQFtDMHX1XCixVkbrjz4jrTNJN4kqNY8vkjNE0ezsUm0/ydCZYY994xmKe3ZN4ECO9bBj3obu1zsDg==","signature_status":"signed_v1","signed_at":"2026-07-05T00:43:37.350394Z","signed_message":"canonical_sha256_bytes"},"source_id":"1909.08847","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ee3eee5ac0f72e2be7cb5fd93f12191ce15145bfd68f04f7abfe902f74a0e4d6","sha256:cfa3f8f7a864f9095901947ee8c5a946179626ce118f7451e16891251d615b29"],"state_sha256":"db371140ebbac844a21637d074b7915daa897cbe491356a3111a2f1549a386fe"}