1997/07/24 by D. Boyanovsky, D. Cormier, Boyanovsky, D. +8
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Astrophysics (astro-ph) #Cosmology and Gravitation Theories #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #Solar and Space Plasma Dynamics #astro-ph #gr-qc #hep-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9707267
26 pages, 5 epsf figures, to appear in the Proceedings of SEWM'97
arxiv created 1997/07/24 · openalex publication_date 1997/07/24 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The physics of the inflationary universe requires the study of the out of equilibrium evolution of quantum fields in curved spacetime. We present the evolution for both the geometry and the matter (described by the quantum inflaton field) by means of the non-perturbative large N limit combined with semi-classical gravitational dynamics including the back-reaction of quantum fluctuations self-consistently for a new inflation scenario. We provide a criterion for the validity of the classical approximation and a full analysis of the case in which spinodal quantum fluctuations drive the evolution of the scale factor. Under carefully determined conditions, we show that the full field equations may be well approximated by those of a single composite field which obeys the classical equation of motion in all cases. The de Sitter stage is found to be followed by a matter dominated phase. We compute the spectrum of scalar density perturbations and argue that the spinodal instabilities are responsible for a `red' spectrum with more power at longer wavelengths. A criterion for the validity of these models is provided and contact with the reconstruction program is established.