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Combining large-scale agent-based simulations with a coarse-grained continuum description, we demonstrate that rotating chiral states emerging from antisymmetric couplings are destroyed by the proliferation of topological defects. The resulting dynamics is spatiotemporally chaotic and characterized by a finite correlation length that diverges as nonreciprocity vanishes. On length scales below this cutoff, density and orientational order fluctuations remain scale-free, but the associated scaling exhibits nonuniversal exponents. We attribute this atypical behavior to the coupling between density and order, which causes topological defects to act as persistent sources of nonlinear fluctuations.<\/jats:p>","DOI":"10.1103\/c6dy-38z1","type":"journal-article","created":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T17:15:26Z","timestamp":1781630126000},"update-policy":"https:\/\/doi.org\/10.1103\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Breakdown of Emergent Chiral Order and Defect Chaos in Nonreciprocal Flocks"],"prefix":"10.1103","volume":"137","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-1802-6866","authenticated-orcid":true,"given":"Charlotte","family":"Myin","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/0087djs12","id-type":"ROR","asserted-by":"publisher"}],"name":"Max Planck Institute for Dynamics and Self-Organization 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All rights are reserved, including those for text and data mining, AI training, and similar technologies.","name":"copyright_statement","label":"Copyright statement","group":{"name":"copyright","label":"copyright"}},{"value":"2026","name":"copyright_year","label":"Copyright year","group":{"name":"copyright","label":"copyright"}},{"value":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/","name":"creative_commons_license","label":"Creative Commons license","group":{"name":"licenses","label":"Licenses"}},{"value":"\u00a92026 The authors","name":"copyright_holder","label":"Copyright holder","group":{"name":"copyright","label":"copyright"}}],"article-number":"118302"}}