{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2019:ISVJ3ZXMPRFKPFSV4D6E2GNQEC","short_pith_number":"pith:ISVJ3ZXM","schema_version":"1.0","canonical_sha256":"44aa9de6ec7c4aa79655e0fc4d19b020855ef625e5b905c94d74c3343562e23e","source":{"kind":"arxiv","id":"1907.03492","version":4},"attestation_state":"computed","paper":{"title":"Inertia drives a flocking phase transition in viscous active fluids","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.bio-ph","physics.flu-dyn"],"primary_cat":"cond-mat.soft","authors_text":"Navdeep Rana, Prasad Perlekar, R. Aditi Simha, Rayan Chatterjee, Sriram Ramaswamy","submitted_at":"2019-07-08T10:21:07Z","abstract_excerpt":"How fast must an oriented collection of extensile swimmers swim to escape the instability of viscous active suspensions? We show that the answer lies in the dimensionless combination $R=\\rho v_0^2/2\\sigma_a$, where $\\rho$ is the suspension mass density, $v_0$ the swim speed and $\\sigma_a$ the active stress. Linear stability analysis shows that for small $R$ disturbances grow at a rate linear in their wavenumber $q$, and that the dominant instability mode involves twist. The resulting steady state in our numerical studies is isotropic hedgehog-defect turbulence. Past a first threshold $R$ of or"},"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":"1907.03492","kind":"arxiv","version":4},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.soft","submitted_at":"2019-07-08T10:21:07Z","cross_cats_sorted":["physics.bio-ph","physics.flu-dyn"],"title_canon_sha256":"8f0f0c208f9d6ea02e67be7bed8f7119fa593258f4667553a936a952b7a624a5","abstract_canon_sha256":"f046772e5132d5677e7d4472bed7b4f6dd9231411dc73d2e6cfe826565463e55"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:29:27.170665Z","signature_b64":"aPf6Fn3tWK8oVOqdE+HS0Em9bgf4R4OlDddA96hx9X+4NPZsa69/Nf79JkpwcH44U+aedBXkyT5YSSx2K8ewBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"44aa9de6ec7c4aa79655e0fc4d19b020855ef625e5b905c94d74c3343562e23e","last_reissued_at":"2026-07-05T03:29:27.170217Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:29:27.170217Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Inertia drives a flocking phase transition in viscous active fluids","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.bio-ph","physics.flu-dyn"],"primary_cat":"cond-mat.soft","authors_text":"Navdeep Rana, Prasad Perlekar, R. Aditi Simha, Rayan Chatterjee, Sriram Ramaswamy","submitted_at":"2019-07-08T10:21:07Z","abstract_excerpt":"How fast must an oriented collection of extensile swimmers swim to escape the instability of viscous active suspensions? We show that the answer lies in the dimensionless combination $R=\\rho v_0^2/2\\sigma_a$, where $\\rho$ is the suspension mass density, $v_0$ the swim speed and $\\sigma_a$ the active stress. Linear stability analysis shows that for small $R$ disturbances grow at a rate linear in their wavenumber $q$, and that the dominant instability mode involves twist. The resulting steady state in our numerical studies is isotropic hedgehog-defect turbulence. Past a first threshold $R$ of or"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1907.03492","kind":"arxiv","version":4},"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/1907.03492/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":"1907.03492","created_at":"2026-07-05T03:29:27.170271+00:00"},{"alias_kind":"arxiv_version","alias_value":"1907.03492v4","created_at":"2026-07-05T03:29:27.170271+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1907.03492","created_at":"2026-07-05T03:29:27.170271+00:00"},{"alias_kind":"pith_short_12","alias_value":"ISVJ3ZXMPRFK","created_at":"2026-07-05T03:29:27.170271+00:00"},{"alias_kind":"pith_short_16","alias_value":"ISVJ3ZXMPRFKPFSV","created_at":"2026-07-05T03:29:27.170271+00:00"},{"alias_kind":"pith_short_8","alias_value":"ISVJ3ZXM","created_at":"2026-07-05T03:29:27.170271+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":1,"internal_anchor_count":1,"sample":[{"citing_arxiv_id":"1908.06247","citing_title":"Transition to Turbulence in Driven Active Matter","ref_index":32,"is_internal_anchor":true}]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC","json":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC.json","graph_json":"https://pith.science/api/pith-number/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/graph.json","events_json":"https://pith.science/api/pith-number/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/events.json","paper":"https://pith.science/paper/ISVJ3ZXM"},"agent_actions":{"view_html":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC","download_json":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC.json","view_paper":"https://pith.science/paper/ISVJ3ZXM","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1907.03492&json=true","fetch_graph":"https://pith.science/api/pith-number/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/graph.json","fetch_events":"https://pith.science/api/pith-number/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/action/timestamp_anchor","attest_storage":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/action/storage_attestation","attest_author":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/action/author_attestation","sign_citation":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/action/citation_signature","submit_replication":"https://pith.science/pith/ISVJ3ZXMPRFKPFSV4D6E2GNQEC/action/replication_record"}},"created_at":"2026-07-05T03:29:27.170271+00:00","updated_at":"2026-07-05T03:29:27.170271+00:00"}