{"paper":{"title":"Correlation Geometry of Quantum Sensor Networks: Local-Global Information Flow and Local Privacy","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Chuan-Feng Li, Geng Chen, Gong-Chu Li, Guang-Can Guo, Hua-Qing Xu, Jia-Hao Zhao, Lei Chen, Si-Qi Zhang, Xu-Song Hong, Yuancheng Liu","submitted_at":"2026-08-07T07:21:39Z","abstract_excerpt":"Quantum sensor networks typically encode N unknown parameters while targeting a single linear combination, rendering the N-1 remaining parameters as nuisance directions. To rigorously quantify estimation precision under such nuisances, we introduce the concept of effective quantum Fisher information (EQFI) and develop an exact EQFI-based phase map that systematically describes the allocation between local and global EQFI. Leveraging this geometric framework, we identify a fundamental bottleneck termed the \"barrel effect\": the global EQFI is strictly bounded by the weakest weighted local sensin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.06888","kind":"arxiv","version":1},"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/2608.06888/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"}