Cosmological perturbations in transient phantom inflation scenarios

• Published in: The European physical journal. C, Particles and fields Vol. 77; no. 1; p. 1
• Main Authors: Richarte, Martín G., Kremer, Gilberto M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2017; Springer; Springer Nature B.V
• Subjects: Analysis; Astronomy; Astrophysics and Cosmology; Elementary Particles; Hadrons; Heavy Ions; Inflation (Economics); Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Regular Article - Theoretical Physics; String Theory; Classical Perturbation; Cosmic Time; Phantom Model; Phantom Divide; Curvature Perturbation
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-017-4629-8

We present a model of inflation where the inflaton is accommodated as a phantom field which exhibits an initial transient pole behavior and then decays into a quintessence field which is responsible for a radiation era. We must stress that the present unified model only deals with a single field and that the transition between the two eras is achieved in a smooth way, so the model does not suffer from the eternal inflation issue. We explore the conditions for the crossing of the phantom divide line within the inflationary era along with the structural stability of several critical points. We study the behavior of the phantom field within the slow-climb approximation along with the necessary conditions to have sufficient inflation. We also examine the model at the level of classical perturbations within the Newtonian gauge and determine the behavior of the gravitational potential, contrast density and perturbed field near the inflation stage and the subsequent radiation era.