{"paper":{"title":"Dynamical Cosmological Constant from A Very Recent Phase Transition","license":"","headline":"","cross_cats":["astro-ph"],"primary_cat":"hep-ph","authors_text":"John McDonald (Glasgow)","submitted_at":"2000-07-12T14:31:32Z","abstract_excerpt":"Observation indicates that the expansion of the Universe is accelerating and favours a dynamical cosmological constant, \\Lambda(t). We consider the possibility that this is due to a scalar field which has undergone a very recent phase transition. We study a simple class of model, corresponding to a \\phi^4 potential with a time-dependent mass squared term. For the models considered the phase transition occurs at a red shift z \\leq 1.2. The evolution of the equation of state \\omega_{\\phi} and energy density \\rho_{\\phi} with time is distinct from existing dynamical \\Lambda models based on slowly "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0007117","kind":"arxiv","version":4},"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"}