{"paper":{"title":"Density-protected states in active matter under virtual confinement","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Dry active nematics under circular virtual confinement self-assemble into dense boundary rings that enclose a disordered core with self-selected density independent of global particle number.","cross_cats":[],"primary_cat":"cond-mat.soft","authors_text":"Beno\\^it Mahault, Francesco Ginelli, Giuseppe Fava","submitted_at":"2026-04-27T09:40:58Z","abstract_excerpt":"We investigate photo-responsive structure formation in a minimal model of dry active nematics. Combining microscopic simulations with the analysis of the corresponding hydrodynamic theory, we show that the system generically self-assembles into a dense, nematically ordered ring at the boundary of compact illumination patterns. Remarkably, this boundary structure gives rise to a disordered core whose density is self-selected and independent of the global particle density. Our analysis reveals that these protected states emerge from a generic interplay between local nematic alignment and curvatu"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"the system generically self-assembles into a dense, nematically ordered ring at the boundary of circular illumination patterns. Remarkably, these boundary structures give rise to a protected disordered core whose density is self-selected and independent of the global particle density.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the minimal model of dry active nematics and the corresponding hydrodynamic theory accurately capture the essential physics of photo-responsive behavior and that the observed states emerge generically rather than as simulation artifacts.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Dry active nematics under circular illumination self-assemble into a dense nematically ordered ring at the boundary that protects a disordered core with self-selected density independent of global density.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Dry active nematics under circular virtual confinement self-assemble into dense boundary rings that enclose a disordered core with self-selected density independent of global particle number.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"4865bce9cfa87f46dcdc1bd36a9a14848744259705d83963e8ff5a6ad74ee56f"},"source":{"id":"2604.24232","kind":"arxiv","version":2},"verdict":{"id":"50b811d9-37ce-4eaf-a8d1-47e63b164135","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-07T17:38:42.535271Z","strongest_claim":"the system generically self-assembles into a dense, nematically ordered ring at the boundary of circular illumination patterns. Remarkably, these boundary structures give rise to a protected disordered core whose density is self-selected and independent of the global particle density.","one_line_summary":"Dry active nematics under circular illumination self-assemble into a dense nematically ordered ring at the boundary that protects a disordered core with self-selected density independent of global density.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the minimal model of dry active nematics and the corresponding hydrodynamic theory accurately capture the essential physics of photo-responsive behavior and that the observed states emerge generically rather than as simulation artifacts.","pith_extraction_headline":"Dry active nematics under circular virtual confinement self-assemble into dense boundary rings that enclose a disordered core with self-selected density independent of global particle number."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.24232/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"ai_meta_artifact","ran_at":"2026-05-21T07:35:41.483307Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-19T22:17:05.691121Z","status":"completed","version":"1.0.0","findings_count":0}],"snapshot_sha256":"6e47875744b2d121ce76796e54cf7457d7c06ec8409d452b99b7d73a28bb18f1"},"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"}