Parametric Amplification of Density Perturbation in the Oscillating inflation

Abstract

We study the adiabatic density perturbation in the {\it oscillating inflation}, proposed by Damour and Mukhanov. The recent study of the cosmological perturbation during reheating shows that the adiabatic fluctuation behaves like as the perfect fluid and no significant amplification occurs on super-horizon scales. In the oscillating inflation, however, the accelerated expansion takes place during the oscillating stage and there might be a possibility that the parametric amplification on small scales affects the adiabatic long-wavelength perturbation. We analytically show that the density perturbation neglecting the metric perturbation can be amplified by the parametric resonance and the instability band becomes very broad during the oscillating inflation. We examined this issue by solving the evolution equation for perturbation numerically. We found that the parametric resonance is strongly suppressed for the long wave modes comparable to the Hubble horizon. The result indicates that the metric perturbation plays a crucial role for the evolution of scalar field perturbation. Therefore, in the single field case, there would be no significant imprint of the oscillating inflation on the primordial spectrum of the adiabatic perturbation. However, it could be expected that the oscillating inflation in the multi-field system gives the enormous amplification on large scales, which may lead to the production of the primordial black holes.

11 pages, 5 Encapsulated postscript figures, RevTeX, submitted to Phys.Rev.D

References in corpus (1)

• Inflation during oscillations of the inflaton

Cited by in corpus (32)

• New cosmological constraints on primordial black holes
• Primordial Black Holes as Dark Matter
• The First Three Seconds: a Review of Possible Expansion Histories of the Early Universe
• Baryon Asymmetry, Dark Matter, and Density Perturbation from PBH
• Curvature perturbation at the local extremum of the inflaton's potential
• Identifying the most crucial parameters of the initial curvature profile for primordial black hole formation
• Dynamical and Gravitational Instability of Oscillating-Field Dark Energy and Dark Matter
• Constraining the primordial black hole abundance with 21cm cosmology
• Supermassive black holes formed by direct collapse of inflationary perturbations
• Baryon asymmetry from primordial black holes
• Reheating the Universe Once More: The Dissipation of Acoustic Waves as a Novel Probe of Primordial Inhomogeneities on Even Smaller Scales
• Cosmological perturbations in coherent oscillating scalar field models
• Slow-Roll Suppression of Adiabatic Instabilities in Coupled Scalar Field-Dark Matter Models
• Primordial black hole formation with full numerical relativity
• Probing the effects of primordial black holes on 21-cm EDGES signal along with interacting dark energy and dark matter - baryon scattering
• What happens when the inflaton stops during inflation
• Self-consistent initial conditions for primordial black hole formation
• Bounds on abundance of primordial black hole and dark matter from EDGES 21-cm signal
• The double formation of primordial black holes
• Parametric phenomena of the particle dynamics in a periodic gravitational wave field
• Power-law modulation of the scalar power spectrum from a heavy field with a monomial potential
• Warm inflation with an oscillatory inflaton in the non-minimal kinetic coupling model
• Full nonlinear growing and decaying modes of superhorizon curvature perturbations
• Global 21-cm brightness temperature in viscous dark energy models
• Ambiguity in running spectral index with an extra light field during inflation
• Inflation in Weyl Scaling Invariant Gravity with $R^3$ Extensions
• Some Remarks on Oscillating Inflation
• Boltzmann equations for preheating
• Large Scale Cosmic Perturbation from Evaporation of Primordial Black Holes
• Particle production in the oscillating inflation model
• Consistency of Anisotropic Inflation during Rapid Oscillations with Planck 2015 Data
• Quantum Remnant as Dark Energy and Dark Matter