Primordial flat frame

• Verfasst von: Wetterich, Christof [VerfasserIn]
• Titel: Primordial flat frame
• Titelzusatz: a new view on inflation
• Verf.angabe: C. Wetterich
• E-Jahr: 2021
• Jahr: 13 October 2021
• Umfang: 36 S.
• Fussnoten: Gesehen am 17.11.2021
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2021
• Band/Heft Quelle: 104(2021), 8, Artikel-ID 083525, Seite 1-36
• ISSN Quelle: 2470-0029
• DOI: doi:10.1103/PhysRevD.104.083525
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1777664535

Abstract

Models of inflationary cosmology admit a choice of the metric for which the geometry of homogeneous isotropic solutions becomes flat Minkowski space in the infinite past. In this primordial flat frame all mass scales vanish in the infinite past and quantum scale symmetry is realized. The cosmological evolution is dominantly described by the slow increase of a scalar field which sets the scale of all masses. We construct the primordial flat frame for standard models of inflation as Starobinsky inflation or chaotic inflation. In particular, we discuss the evolution of inhomogeneous solutions in the neighborhood of the homogeneous isotropic background solution and their relation to the observable primordial fluctuation spectrum. If the propagators for the graviton and scalar field remain regular, our observed inhomogeneous universe can be extrapolated back to the infinite past in physical time. In this case there is no physical big-bang singularity—the latter reflects only a singular choice of “field coordinates.” Independently of the issue of singularity the primordial flat frame offers a new view on the physical properties of the inflationary universe, which can be characterized as a very slowly evolving almost empty “vacuum” state with approximate scale symmetry.