{"paper":{"title":"Numerical simulations of density perturbation and gravitational wave production from cosmological first-order phase transition","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Lattice simulations show bubble wall motion dominates density perturbations for strong first-order phase transitions while vacuum decay delays dominate for weak ones.","cross_cats":["astro-ph.CO","hep-th"],"primary_cat":"hep-ph","authors_text":"Jintao Zou, Ligong Bian, Zhiqing Zhu, Zizhuo Zhao","submitted_at":"2025-02-27T15:04:55Z","abstract_excerpt":"We conducted three-dimensional lattice simulations to study the density perturbation and gravitational waves (GWs) during first-order phase transition (FOPT). We find that for phase transition strength $\\alpha > 1$, the forward motion of bubble walls becomes the primary source, whereas for $\\alpha < 1$, the dominant contribution to the density perturbation comes from the delay of vacuum decay. Additionally, the power spectrum of density perturbations generated by the phase transition exhibits a slope of $k^3$ at small wavenumbers and $k^{-1.5}$ at large wavenumbers. Furthermore, we calculated "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"For phase transition strength α > 1, forward motion of bubble walls is the primary source of density perturbation, while for α < 1, the dominant contribution comes from the delay of vacuum decay; the density perturbation power spectrum has slope k^3 at small k and k^{-1.5} at large k; GW spectrum has k^3 and k^{-2}.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The lattice simulations accurately capture the non-linear dynamics of bubble wall motion and vacuum decay without significant numerical artifacts or missing physical effects like friction or plasma interactions.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Lattice simulations show bubble wall motion dominates density perturbations for strong first-order phase transitions while vacuum decay delays dominate for weak ones.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"7a54e918fb8c1cefe2d1ed8efb80c919a5cf86765abad96ba1a389dc3575880f"},"source":{"id":"2502.20166","kind":"arxiv","version":4},"verdict":{"id":"0ccac975-86a6-4e3c-89c9-1fbf5929b1ae","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-23T02:30:30.540831Z","strongest_claim":"For phase transition strength α > 1, forward motion of bubble walls is the primary source of density perturbation, while for α < 1, the dominant contribution comes from the delay of vacuum decay; the density perturbation power spectrum has slope k^3 at small k and k^{-1.5} at large k; GW spectrum has k^3 and k^{-2}.","one_line_summary":"3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The lattice simulations accurately capture the non-linear dynamics of bubble wall motion and vacuum decay without significant numerical artifacts or missing physical effects like friction or plasma interactions.","pith_extraction_headline":"Lattice simulations show bubble wall motion dominates density perturbations for strong first-order phase transitions while vacuum decay delays dominate for weak ones."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2502.20166/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":111,"sample":[{"doi":"","year":null,"title":"As more and more bubbles form and collide, the initially uniform spatial structure is disrupted, resulting in an asymmetric energy distribution","work_id":"30212fe1-0d5e-4c74-ae7d-a74628ca4377","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1982,"title":"S. W. Hawking, I. G. Moss, and J. M. Stewart, Bubble Collisions in the Very Early Universe, Phys. Rev. D26, 2681 (1982)","work_id":"2878448f-d156-4fa1-9bad-e451a81d90f4","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1982,"title":"M. Crawford and D. N. Schramm, Spontaneous Generation of Density Perturbations in the Early Universe, Nature298, 538 (1982)","work_id":"17e2d00d-e843-4073-a600-db18b2e17b51","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":1979,"title":"H. Kodama, M. Sasaki, and K. Sato, Abundance of Primordial Holes Produced by Cosmological First Order Phase Transition, Prog. Theor. Phys.68, 1979 (1982)","work_id":"5bf46d92-6bf5-4857-925e-4e7c8719d591","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2012,"title":"Determining the outcome of cosmic bubble collisions in full General Relativity","work_id":"12b1dfc2-b395-4f2c-b733-72ff34a6c0dc","ref_index":5,"cited_arxiv_id":"1112.4487","is_internal_anchor":true}],"resolved_work":111,"snapshot_sha256":"f17f90b1eb6e5b9639378689bc9565a407a5a5b4da19db7e55304e208a2e4c4c","internal_anchors":43},"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"}