Quantum fluctuations and semiclassicality in an inflaton-driven evolution

Autor: Brizuela, David, Pawlowski, Tomasz
Rok vydání: 2021
Předmět:
Zdroj: JCAP 10 (2022) 080
Druh dokumentu: Working Paper
DOI: 10.1088/1475-7516/2022/10/080
Popis: A semiclassical description of quantum systems is applied to probe the dynamics of the cosmological model of an inflationary universe with quadratic inflaton potential, described in a quantum framework of geometrodynamics. The systematic analysis, focusing in particular on the inflationary and post-inflationary epochs, revealed several surprising and counterintuitive features: $(i)$ during inflation the universe rapidly spreads out in volume which leads to significant relative variance by the end of inflation; $(ii)$ despite that, the quantum evolution can still be described to high accuracy by semiclassical methods; $(iii)$ moreover, in the post-inflationary epoch, as the order of included quantum corrections increases, the quantum trajectory approaches the classical one and the description involving second-order corrections only is actually the least accurate there. The consequence of the latter is that the effects of the quantum variances are washed out by the higher-order quantum corrections.
Comment: Expanded version of the paper accepted for publication in JCAP. We have included a more detailed derivation of the model, some clarifications on the presentation of the results, and several new references
Databáze: arXiv