{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2012:7OPFFYZCQVDPFEMWLN7RCJEQMU","short_pith_number":"pith:7OPFFYZC","schema_version":"1.0","canonical_sha256":"fb9e52e3228546f291965b7f11249065329af68578eaaab54efb779018f41b43","source":{"kind":"arxiv","id":"1202.4317","version":1},"attestation_state":"computed","paper":{"title":"Equation of State for Dark Energy in Modified Gravity Theories","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"gr-qc","authors_text":"Kazuharu Bamba","submitted_at":"2012-02-20T13:23:45Z","abstract_excerpt":"We explore the equation of state (EoS) for dark energy $w_{\\mathrm{DE}}$ in modified gravitational theories to explain the current accelerated expansion of the universe. We explicitly demonstrate that the future crossings of the phantom divide line of $w_{\\mathrm{DE}}=-1$ are the generic feature in the existing viable $f(R)$ gravity models. Furthermore, we show that the crossing of the phantom divide can be realized in the combined $f(T)$ theory constructed with the exponential and logarithmic terms. In addition, we investigate the effective EoS for the universe when the finite-time future sin"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1202.4317","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2012-02-20T13:23:45Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"e5315f17ad555adb426113abe52fa0380cf0da36abaa23be4ceb3d545ea76e68","abstract_canon_sha256":"39f4d761a2c6fbfa303e23dd18b86bab105bcf7cdab6e82e2f3368227de2012f"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:37:02.915078Z","signature_b64":"Gmm+oJEM1a1aAXYk0ftprTGNffH91ktqDMctVSbE8h/gkdWPyyElWgInE/FNnuSDdbRF7mrmaLDx2KClnVWDDQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fb9e52e3228546f291965b7f11249065329af68578eaaab54efb779018f41b43","last_reissued_at":"2026-05-18T00:37:02.914467Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:37:02.914467Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Equation of State for Dark Energy in Modified Gravity Theories","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"gr-qc","authors_text":"Kazuharu Bamba","submitted_at":"2012-02-20T13:23:45Z","abstract_excerpt":"We explore the equation of state (EoS) for dark energy $w_{\\mathrm{DE}}$ in modified gravitational theories to explain the current accelerated expansion of the universe. We explicitly demonstrate that the future crossings of the phantom divide line of $w_{\\mathrm{DE}}=-1$ are the generic feature in the existing viable $f(R)$ gravity models. Furthermore, we show that the crossing of the phantom divide can be realized in the combined $f(T)$ theory constructed with the exponential and logarithmic terms. In addition, we investigate the effective EoS for the universe when the finite-time future sin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1202.4317","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1202.4317","created_at":"2026-05-18T00:37:02.914575+00:00"},{"alias_kind":"arxiv_version","alias_value":"1202.4317v1","created_at":"2026-05-18T00:37:02.914575+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1202.4317","created_at":"2026-05-18T00:37:02.914575+00:00"},{"alias_kind":"pith_short_12","alias_value":"7OPFFYZCQVDP","created_at":"2026-05-18T12:26:58.693483+00:00"},{"alias_kind":"pith_short_16","alias_value":"7OPFFYZCQVDPFEMW","created_at":"2026-05-18T12:26:58.693483+00:00"},{"alias_kind":"pith_short_8","alias_value":"7OPFFYZC","created_at":"2026-05-18T12:26:58.693483+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU","json":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU.json","graph_json":"https://pith.science/api/pith-number/7OPFFYZCQVDPFEMWLN7RCJEQMU/graph.json","events_json":"https://pith.science/api/pith-number/7OPFFYZCQVDPFEMWLN7RCJEQMU/events.json","paper":"https://pith.science/paper/7OPFFYZC"},"agent_actions":{"view_html":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU","download_json":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU.json","view_paper":"https://pith.science/paper/7OPFFYZC","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1202.4317&json=true","fetch_graph":"https://pith.science/api/pith-number/7OPFFYZCQVDPFEMWLN7RCJEQMU/graph.json","fetch_events":"https://pith.science/api/pith-number/7OPFFYZCQVDPFEMWLN7RCJEQMU/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU/action/timestamp_anchor","attest_storage":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU/action/storage_attestation","attest_author":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU/action/author_attestation","sign_citation":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU/action/citation_signature","submit_replication":"https://pith.science/pith/7OPFFYZCQVDPFEMWLN7RCJEQMU/action/replication_record"}},"created_at":"2026-05-18T00:37:02.914575+00:00","updated_at":"2026-05-18T00:37:02.914575+00:00"}