{"paper":{"title":"Long-wavelength density response and momentum resolution in strange-metal charge spectroscopy","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["cond-mat.supr-con"],"primary_cat":"cond-mat.str-el","authors_text":"Ilmo Sung","submitted_at":"2026-07-23T11:21:14Z","abstract_excerpt":"Momentum-resolved electron energy-loss spectroscopy (EELS) on strange-metal Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (Bi-2212) observes a broad charge continuum that is nearly momentum independent over an extended finite-momentum regime, whereas optical spectroscopy determines a metallic local conductivity. We analyze the long-wavelength response function that connects these regimes: the proper homogeneous bulk charge-density polarization. For any homogeneous $U(1)$-conserving metal whose longitudinal matter conductivity remains finite in the $q\\to0$ limit at fixed nonzero frequency, the Ward identity gi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.21206","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/2607.21206/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"}