{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"12c41cf304e778dba3af0ac23e2e34d8ad1e1d187be096be25ae5cda34c7e588","created":"2026-10-03T07:17:56Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"73f8e6ffdfc769d1768557054dedce3aa16d75c570505650efeb4fff2b22613f","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"bio.active-matter.active-nematic-order","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Active nematics are layers of elongated self-driven units that line up without a preferred head or tail. Whether such a layer stays orientationally ordered over large distances, or activity always creates enough defects to destroy the order, is disputed.","posed_since":"","precise":"In $2\\mathrm{D}$ dry active nematics (no momentum conservation, e.g. Chate-Ginelli-Montagne-type particle models), determine whether the ordered phase has quasi-long-range orientational order with algebraically decaying correlations, or whether activity unbinds $+1/2$ and $-1/2$ disclinations at any finite activity so that order is lost beyond a finite length. An answer gives the asymptotic form of the orientational correlation function and the defect density versus system size.","problem_ref":null,"references":"","settled_by":"Simulations over several decades of system size measuring orientational correlations and defect density, together with a renormalization-group treatment including defects.","status_note":"","title":"Do two-dimensional dry active nematics keep quasi-long-range order","topic_ref":"6a008dc19304a289e116a6d6e6371cc6de0ef3d1a904e572d5454f039b2ac217"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"073fe63cc8ce83edfa9dd5d85ca5a5bbcc22810208930719e12ee3dcb8ea287a","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"cf036af4668c8a3d26507b6f78dc80d0eb89c914f686f59223deeb9073eea6aa","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"LTyvBlUc8Cy3LY4_9WL-H-9u5ioJkNrumLfWovnW3kijKUbEnu_P36nQg_TZ6xHeaS2JpAUvbYsUn-cX2FTtDQ"},"schema":"pubphys.envelope/1"},"record_hash":"073fe63cc8ce83edfa9dd5d85ca5a5bbcc22810208930719e12ee3dcb8ea287a","leaf_index":719}