{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:K3JGCOTQXQB6GZOVOPLHI2YL33","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"4398df19c853c569d3c6f0d5d07745578b8053ebeae1cbe10c2f70a794f962a6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.quant-gas","submitted_at":"2018-04-11T14:56:28Z","title_canon_sha256":"57429f0730505deb05d87800b8c1ca92d0074a77f5cf540377f6056dac8ea6be"},"schema_version":"1.0","source":{"id":"1804.04032","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1804.04032","created_at":"2026-05-18T00:03:56Z"},{"alias_kind":"arxiv_version","alias_value":"1804.04032v2","created_at":"2026-05-18T00:03:56Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1804.04032","created_at":"2026-05-18T00:03:56Z"},{"alias_kind":"pith_short_12","alias_value":"K3JGCOTQXQB6","created_at":"2026-05-18T12:32:33Z"},{"alias_kind":"pith_short_16","alias_value":"K3JGCOTQXQB6GZOV","created_at":"2026-05-18T12:32:33Z"},{"alias_kind":"pith_short_8","alias_value":"K3JGCOTQ","created_at":"2026-05-18T12:32:33Z"}],"graph_snapshots":[{"event_id":"sha256:3c8ca10f1beba32b847f83ea2fa1f8416b707d6e0761d0e53b9d537c13632afe","target":"graph","created_at":"2026-05-18T00:03:56Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Using linear response theory within the Random Phase Approximation, we investigate the propagation of sound in a uniform two dimensional (2D) Bose gas in the collisionless regime. We show that the sudden removal of a static density perturbation produces a damped oscillatory behavior revealing that sound can propagate also in the absence of collisions, due to mean-field interaction effects. Our analysis points out the crucial role played by Landau damping. We support our predictions by performing numerical simulations with the stochastic (projected) Gross-Pitaevskii equation. The results are co","authors_text":"Fabrizio Larcher, Franco Dalfovo, Lev Pitaevskii, Miki Ota, Nikolaos P. Proukakis, Sandro Stringari","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.quant-gas","submitted_at":"2018-04-11T14:56:28Z","title":"Collisionless sound in a uniform two-dimensional Bose gas"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.04032","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:212cbbcdc8d78e1a052c99507081bdfbc2099066f8dfabcb3a09119c233b562f","target":"record","created_at":"2026-05-18T00:03:56Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"4398df19c853c569d3c6f0d5d07745578b8053ebeae1cbe10c2f70a794f962a6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.quant-gas","submitted_at":"2018-04-11T14:56:28Z","title_canon_sha256":"57429f0730505deb05d87800b8c1ca92d0074a77f5cf540377f6056dac8ea6be"},"schema_version":"1.0","source":{"id":"1804.04032","kind":"arxiv","version":2}},"canonical_sha256":"56d2613a70bc03e365d573d6746b0bdeea23cf25e2d88cb56215a214bdff349f","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"56d2613a70bc03e365d573d6746b0bdeea23cf25e2d88cb56215a214bdff349f","first_computed_at":"2026-05-18T00:03:56.168168Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:03:56.168168Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"9BcBlIgKHyJoczSDwgUzEn3XaDPBK25AgR+M2Is3ybr7pFPVH02lP6rXPp9EEqF4XxkjxZktwwVj+GnD6faiBQ==","signature_status":"signed_v1","signed_at":"2026-05-18T00:03:56.168770Z","signed_message":"canonical_sha256_bytes"},"source_id":"1804.04032","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:212cbbcdc8d78e1a052c99507081bdfbc2099066f8dfabcb3a09119c233b562f","sha256:3c8ca10f1beba32b847f83ea2fa1f8416b707d6e0761d0e53b9d537c13632afe"],"state_sha256":"cd1b40083edac434c925faf3982e0c014fb6edcb6a9fee1e0f5d6b04d2288b12"}