{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2023:BHCOSYS5OZ7HP6HCW37PS2D4EN","short_pith_number":"pith:BHCOSYS5","schema_version":"1.0","canonical_sha256":"09c4e9625d767e77f8e2b6fef9687c2344b90277beaaba7e4196ef7923ce6ca0","source":{"kind":"arxiv","id":"2308.08546","version":2},"attestation_state":"computed","paper":{"title":"What is the source of the PTA GW signal?","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["hep-th"],"primary_cat":"astro-ph.CO","authors_text":"Antonio Iovino Jr., Gabriele Franciolini, Gert H\\\"utsi, Hardi Veerm\\\"ae, John Ellis, Juan Urrutia, Malcolm Fairbairn, Marek Lewicki, Martti Raidal, Ville Vaskonen","submitted_at":"2023-08-16T17:59:15Z","abstract_excerpt":"The most conservative interpretation of the nHz stochastic gravitational wave background (SGWB) discovered by NANOGrav and other Pulsar Timing Array (PTA) Collaborations is astrophysical, namely that it originates from supermassive black hole (SMBH) binaries. However, alternative cosmological models have been proposed, including cosmic strings, phase transitions, domain walls, primordial fluctuations and \"audible\" axions. We perform a multi-model analysis (MMA) to compare how well these different hypotheses fit the NANOGrav data, both in isolation and in combination with SMBH binaries, and add"},"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":"2308.08546","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.CO","submitted_at":"2023-08-16T17:59:15Z","cross_cats_sorted":["hep-th"],"title_canon_sha256":"ad87fd835d29168629934eb767d771fb6a75e41bc42f4bf49a7ebfff272dd6a0","abstract_canon_sha256":"1b4c138fab1174e1a71bb622b8cc26df3346b4992617acbbc63ce059f203592d"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T06:58:41.963855Z","signature_b64":"sUkFctHjIANT1B8gYAXL+FPRCxIMogO5l+p7A2J8TZ2KBG3++efkEsa/2sAZAEoJcrq02KnSu8II5Dt+snnyBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"09c4e9625d767e77f8e2b6fef9687c2344b90277beaaba7e4196ef7923ce6ca0","last_reissued_at":"2026-07-05T06:58:41.963367Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T06:58:41.963367Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"What is the source of the PTA GW signal?","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["hep-th"],"primary_cat":"astro-ph.CO","authors_text":"Antonio Iovino Jr., Gabriele Franciolini, Gert H\\\"utsi, Hardi Veerm\\\"ae, John Ellis, Juan Urrutia, Malcolm Fairbairn, Marek Lewicki, Martti Raidal, Ville Vaskonen","submitted_at":"2023-08-16T17:59:15Z","abstract_excerpt":"The most conservative interpretation of the nHz stochastic gravitational wave background (SGWB) discovered by NANOGrav and other Pulsar Timing Array (PTA) Collaborations is astrophysical, namely that it originates from supermassive black hole (SMBH) binaries. However, alternative cosmological models have been proposed, including cosmic strings, phase transitions, domain walls, primordial fluctuations and \"audible\" axions. We perform a multi-model analysis (MMA) to compare how well these different hypotheses fit the NANOGrav data, both in isolation and in combination with SMBH binaries, and add"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2308.08546","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2308.08546/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2308.08546","created_at":"2026-07-05T06:58:41.963430+00:00"},{"alias_kind":"arxiv_version","alias_value":"2308.08546v2","created_at":"2026-07-05T06:58:41.963430+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2308.08546","created_at":"2026-07-05T06:58:41.963430+00:00"},{"alias_kind":"pith_short_12","alias_value":"BHCOSYS5OZ7H","created_at":"2026-07-05T06:58:41.963430+00:00"},{"alias_kind":"pith_short_16","alias_value":"BHCOSYS5OZ7HP6HC","created_at":"2026-07-05T06:58:41.963430+00:00"},{"alias_kind":"pith_short_8","alias_value":"BHCOSYS5","created_at":"2026-07-05T06:58:41.963430+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":16,"internal_anchor_count":1,"sample":[{"citing_arxiv_id":"2607.07477","citing_title":"Population statistics of nanohertz gravitational wave sources","ref_index":41,"is_internal_anchor":true},{"citing_arxiv_id":"2606.21380","citing_title":"Theoretical consistency and phenomenology of supercooled cosmological phase transitions","ref_index":183,"is_internal_anchor":false},{"citing_arxiv_id":"2605.05157","citing_title":"Are PTA measurements sensitive to gravitational wave non-Gaussianities?","ref_index":10,"is_internal_anchor":false},{"citing_arxiv_id":"2605.27231","citing_title":"A Fast Method to Compute Scalar Induced Gravitational Waves on a Lattice with Primordial Non-Gaussianities","ref_index":29,"is_internal_anchor":false},{"citing_arxiv_id":"2606.00577","citing_title":"Searching for a waveform-agnostic gravitational wave signal in pulsar timing arrays","ref_index":12,"is_internal_anchor":false},{"citing_arxiv_id":"2408.03649","citing_title":"Probing radiative electroweak symmetry breaking with colliders and gravitational waves","ref_index":93,"is_internal_anchor":false},{"citing_arxiv_id":"2503.01962","citing_title":"Curvature Perturbations from First-Order Phase Transitions: Implications to Black Holes and Gravitational Waves","ref_index":101,"is_internal_anchor":false},{"citing_arxiv_id":"2505.16820","citing_title":"Isotropy, anisotropies and non-Gaussianity in the scalar-induced gravitational-wave background: diagrammatic approach for primordial non-Gaussianity up to arbitrary order","ref_index":278,"is_internal_anchor":false},{"citing_arxiv_id":"2512.08301","citing_title":"Isocurvature Induced Gravitational Waves at Pulsar Timing Arrays","ref_index":78,"is_internal_anchor":false},{"citing_arxiv_id":"2605.15197","citing_title":"Primordial Black Hole from Tensor-induced Density Fluctuation: First-order Phase Transitions and Domain Walls","ref_index":118,"is_internal_anchor":false},{"citing_arxiv_id":"2604.26513","citing_title":"Transient Parity Violation during Inflation: Implications for PTA Gravitational Waves","ref_index":12,"is_internal_anchor":false},{"citing_arxiv_id":"2605.05310","citing_title":"Constraints on the inflationary vacuum and reheating era from NANOGrav","ref_index":21,"is_internal_anchor":false},{"citing_arxiv_id":"2605.05157","citing_title":"Are PTA measurements sensitive to gravitational wave non-Gaussianities?","ref_index":10,"is_internal_anchor":false},{"citing_arxiv_id":"2604.08506","citing_title":"The Heavy Tailed Non-Gaussianity of the Supermassive Black Hole Gravitational Wave Background","ref_index":21,"is_internal_anchor":false},{"citing_arxiv_id":"2604.20063","citing_title":"Purely Quadratic Non-Gaussianity from Tachyonic Instability: Primordial Black Holes and Scalar-Induced Gravitational Waves","ref_index":119,"is_internal_anchor":false},{"citing_arxiv_id":"2604.21168","citing_title":"Neutron Portal and Dark Matter-Baryon Coincidence: from UV Completion to Phenomenology","ref_index":28,"is_internal_anchor":false}]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN","json":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN.json","graph_json":"https://pith.science/api/pith-number/BHCOSYS5OZ7HP6HCW37PS2D4EN/graph.json","events_json":"https://pith.science/api/pith-number/BHCOSYS5OZ7HP6HCW37PS2D4EN/events.json","paper":"https://pith.science/paper/BHCOSYS5"},"agent_actions":{"view_html":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN","download_json":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN.json","view_paper":"https://pith.science/paper/BHCOSYS5","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=2308.08546&json=true","fetch_graph":"https://pith.science/api/pith-number/BHCOSYS5OZ7HP6HCW37PS2D4EN/graph.json","fetch_events":"https://pith.science/api/pith-number/BHCOSYS5OZ7HP6HCW37PS2D4EN/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN/action/timestamp_anchor","attest_storage":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN/action/storage_attestation","attest_author":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN/action/author_attestation","sign_citation":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN/action/citation_signature","submit_replication":"https://pith.science/pith/BHCOSYS5OZ7HP6HCW37PS2D4EN/action/replication_record"}},"created_at":"2026-07-05T06:58:41.963430+00:00","updated_at":"2026-07-05T06:58:41.963430+00:00"}