{"paper":{"title":"$N$-coherence vs. $t$-coherence: An alternative route to the Gross-Pitaevskii equation","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.quant-gas","authors_text":"Bettina Gertjerenken, Martin Holthaus","submitted_at":"2015-08-17T19:16:59Z","abstract_excerpt":"We show how a candidate mean-field amplitude can be constructed from the exact wave function of an externally forced $N$-Boson system. The construction makes use of subsidiary $(N-1)$-particle states which are propagated in time in addition to the true $N$-particle state, but does not involve spontaneous breaking of the $U(1)$ symmetry associated with particle number conservation. Provided the flow in Fock space possesses a property which we call maximum stiffness, or $t$-coherence, the candidate amplitude actually satisfies the time-dependent Gross-Pitaevskii equation, and then serves as macr"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.04117","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":""},"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"}