Related papers: Preheating, Parametric Resonance and the Einstein …
In this work, we investigate the preheating mechanism after inflation in general scalar-tensor theories of gravity. In the present scenario, we consider two-field scenario and then derive the potential of exponential and hyperbolic tangent…
We investigate preheating in a higher-dimensional generalized Kaluza-Klein theory with a quadratic inflaton potential $V(\phi)=\frac12 m^2\phi^2$ including metric perturbations explicitly. The system we consider is the multi-field model…
We study the preheating scenario in Generalized Einstein Theories, considering a class of such theories which are conformally equivalent to those of an extra field with a modified potential in the Einstein frame. Resonant creation of bosons…
We consider the nonlinear dynamics of inflaton fragmentation during and after preheating in the simplest model of chaotic inflation. While the earlier regime of parametric resonant particle production and the later turbulent regime of…
Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter.…
An oscillating inflaton field induces small amplitude oscillations of the Hubble parameter at the end of inflation. These Hubble parameter induced oscillations, in turn, trigger parametric particle production of all light fields, even if…
We investigate the cosmological perturbation of two-scalar field model during the reheating phase after inflation. Using the exact solution of the perturbation in long-wavelength limit, which is expressed in terms of the background…
We study the class of two-field inflationary Universe models \lambda\phi^4/4 + g^2\chi^2\phi^2/2, in which parametric resonance during the initial stages of reheating can lead to an exponential amplification of the amplitude of cosmological…
Field amplification and particle production due to parametric resonance are highly nontrivial predictions of quantum fields that couple to an oscillating source during inflation and reheating. Understanding this two effects is crucial for…
The combined Planck, BICEP/Keck Array and BAO measurements of the scalar spectral index and the tensor-to-scalar ratio from the cosmic microwave background observations severely constrain or completely rule out several models of…
At the first stage of reheating after inflation, parametric resonance may rapidly transfer most of the energy of an inflaton field $\phi$ to the energy of other bosons. We show that quantum fluctuations of scalar and vector fields produced…
We study in detail (p)reheating after multi-field inflation models with a particular focus on N-flation. We consider a variety of different couplings between the inflatons and the matter sector, including both quartic and trilinear…
We study the quantum fluctuations of scalar fields with a variable effective mass during an inflationary phase. We consider the situation where the effective mass depends on a background scalar field, which evolves during inflation from…
Metric perturbations typically strengthen field resonances during preheating. In contrast we present a model in which the super-Hubble field resonances are completely {\em suppressed} when metric perturbations are included. The model is the…
The gravitational wave equations form a parametric resonance system during oscillatory reheating after inflation, when cast in terms of the electric and magnetic parts of the Weyl tensor. This is in direct analogy with preheating. For…
After inflation, a period of preheating may have produced a stochastic background of high frequency gravitational waves (GWs) that would persist until today. The nature of the inflaton's coupling to Standard Model or other fields is…
We take an analytic approach towards the framework of parametric resonance and apply it on preheating and locked inflation. A two-scalar toy model is analytically solved for the \lambda\phi^2\chi^2 coupling for the homogenous modes. The…
We consider the scale-invariant inflationary model studied in [1]. The Lagrangian includes all the scale-invariant operators that can be built with combinations of $R$, $R^2$ and one scalar field. The equations of motion show that the…
We use lattice simulations to examine the detailed dynamics of inflaton fragmentation during and after preheating in $\lambda \phi^4$ chaotic inflation. The dynamics are qualitatively similar to preheating after $m^2 \phi^2$ inflation,…
We study preheating after hilltop inflation where the inflaton couples to another scalar field, e.g. a right-handed sneutrino, which provides a mechanism for generating the correct initial conditions for inflation and also a decay channel…