{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2019:35KHHMNLFRGOXDR6T2KSWLX2VG","short_pith_number":"pith:35KHHMNL","schema_version":"1.0","canonical_sha256":"df5473b1ab2c4ceb8e3e9e952b2efaa981272c79e59dd0ecf612fa4a7782c20e","source":{"kind":"arxiv","id":"1901.08679","version":2},"attestation_state":"computed","paper":{"title":"Fourier-series expansion of the dark-energy equation of state","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"David Tamayo, J. Alberto Vazquez","submitted_at":"2019-01-24T23:12:29Z","abstract_excerpt":"The dark energy component of the universe still remains as a mystery, however, several papers based on observational data have shown that its equation of state may have an oscillatory behaviour. In this paper, we provide a general description for the dark-energy equation-of-state $w(z)$ in the form of Fourier series. This description generalises some previous dynamical dark energy models and is in agreement with the $w(z)$ reconstructions. We make use of a modified version of a simple and fast Markov Chain Monte Carlo code to constraint the model parameters. For the analysis we use data from s"},"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":"1901.08679","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2019-01-24T23:12:29Z","cross_cats_sorted":[],"title_canon_sha256":"729212876dbe58bed5c267a96a3961e9885ba7490150ccf1c02f5da195a21501","abstract_canon_sha256":"18fa3844745fd01e549e67cb309a1dd7aa928a365365bb2a2fbc4dde4e54e4b4"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:43:09.133393Z","signature_b64":"5LTh4f2iCylXjo7He+6ZQqWYn3zlflMqLnhK4V5BFaMOqi1XN1Ddl8SC5twDArCb3FT5MR2cVOxPy74RbjYuCw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"df5473b1ab2c4ceb8e3e9e952b2efaa981272c79e59dd0ecf612fa4a7782c20e","last_reissued_at":"2026-05-17T23:43:09.132909Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:43:09.132909Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Fourier-series expansion of the dark-energy equation of state","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"David Tamayo, J. Alberto Vazquez","submitted_at":"2019-01-24T23:12:29Z","abstract_excerpt":"The dark energy component of the universe still remains as a mystery, however, several papers based on observational data have shown that its equation of state may have an oscillatory behaviour. In this paper, we provide a general description for the dark-energy equation-of-state $w(z)$ in the form of Fourier series. This description generalises some previous dynamical dark energy models and is in agreement with the $w(z)$ reconstructions. We make use of a modified version of a simple and fast Markov Chain Monte Carlo code to constraint the model parameters. For the analysis we use data from s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.08679","kind":"arxiv","version":2},"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":"1901.08679","created_at":"2026-05-17T23:43:09.132984+00:00"},{"alias_kind":"arxiv_version","alias_value":"1901.08679v2","created_at":"2026-05-17T23:43:09.132984+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.08679","created_at":"2026-05-17T23:43:09.132984+00:00"},{"alias_kind":"pith_short_12","alias_value":"35KHHMNLFRGO","created_at":"2026-05-18T12:33:07.085635+00:00"},{"alias_kind":"pith_short_16","alias_value":"35KHHMNLFRGOXDR6","created_at":"2026-05-18T12:33:07.085635+00:00"},{"alias_kind":"pith_short_8","alias_value":"35KHHMNL","created_at":"2026-05-18T12:33:07.085635+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/35KHHMNLFRGOXDR6T2KSWLX2VG","json":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG.json","graph_json":"https://pith.science/api/pith-number/35KHHMNLFRGOXDR6T2KSWLX2VG/graph.json","events_json":"https://pith.science/api/pith-number/35KHHMNLFRGOXDR6T2KSWLX2VG/events.json","paper":"https://pith.science/paper/35KHHMNL"},"agent_actions":{"view_html":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG","download_json":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG.json","view_paper":"https://pith.science/paper/35KHHMNL","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1901.08679&json=true","fetch_graph":"https://pith.science/api/pith-number/35KHHMNLFRGOXDR6T2KSWLX2VG/graph.json","fetch_events":"https://pith.science/api/pith-number/35KHHMNLFRGOXDR6T2KSWLX2VG/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG/action/timestamp_anchor","attest_storage":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG/action/storage_attestation","attest_author":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG/action/author_attestation","sign_citation":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG/action/citation_signature","submit_replication":"https://pith.science/pith/35KHHMNLFRGOXDR6T2KSWLX2VG/action/replication_record"}},"created_at":"2026-05-17T23:43:09.132984+00:00","updated_at":"2026-05-17T23:43:09.132984+00:00"}