{"paper":{"title":"Fragmented ETH: Prethermalization, Timescales, and Ensemble Inequivalence","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["quant-ph"],"primary_cat":"cond-mat.stat-mech","authors_text":"C. L. Sriram, Lea F. Santos, Soumya Kanti Pal","submitted_at":"2026-07-16T18:01:07Z","abstract_excerpt":"We investigate how finite quantum systems with strong long-range interactions approach thermal equilibrium. Nearly conserved quantities inherited from the fully connected limit fragment the Hilbert space and give rise to a many-body spectrum split into energy bands. As a result, equilibration becomes anomalously slow and proceeds through long-lived prethermal plateaus. This two-stage equilibration process is, however, not universal. We uncover the mechanism that determines which observables and initial states exhibit, or evade, prethermal plateaus. We also develop a perturbative theory that pr"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.15350","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/2607.15350/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"}