Related papers: Instant Preheating
A simple model for the reheating of the universe after inflation is studied in which an essentially inhomogeneous scalar field representing matter is coupled to an essentially homogeneous scalar inflaton field. Through this coupling, the…
We present a model where inflation and Dark Matter takes place via a single scalar field phi. Without introducing any new parameters we are able unify inflation and Dark Matter using a scalar field phi that accounts for inflation at an…
Cosmological reheating bridges the inflationary epoch and the hot big bang phase, yet its underlying dynamics remain poorly understood. In this work, we investigate a minimal scenario in which the inflaton evolves under a simple power-law…
We study the nonlinear stage of preheating in a model consisting of a single inflaton field $\phi$ nonminimally coupled to the spacetime curvature and considering a self-coupling quartic potential V ($\phi$) = $\lambda \phi^4/4$. As the…
We have tested some simple quintessential inflation models, imposing that they match with the recent observational data provided by the BICEP and Planck's team and leading to a reheating temperature, which is obtained via gravitational…
The paradigm of the inflationary universe provides a possible explanation for several observed cosmological properties. In order for such solutions to be successful, the universe must convert the energy stored in the inflaton potential into…
Whereas preheating after chaotic and hybrid inflation models has been abundantly studied in the literature, preheating in small field inflation models, where the curvature of the inflaton potential is negative during inflation, remains less…
Inflection-point inflation is an interesting possibility to realize a successful slow-roll inflation when inflation is driven by a single scalar field with its initial value below the Planck mass ($\phi_I \lesssim M_{Pl}$). In order for a…
Tachyonic preheating is realized when the inflaton repeatedly returns to a convex region of the potential during the post-inflationary oscillating phase. This will induce a strong tachyonic instability and lead to a rapid fragmentation of…
The inflaton must convert its energy into radiation after inflation, which, in a conventional scenario, is caused by the perturbative inflaton decay. This reheating process would be much more complicated in some cases: the decay products…
We study chaotic dynamics in preheating after inflation in which an inflaton $\phi$ is coupled to another scalar field $\chi$ through an interaction $(1/2)g^2\phi^2\chi^2$. We first estimate the size of the quasi-homogeneous field $\chi$ at…
We investigate whether Effective Field Theory (EFT) approaches, which have been useful in examining inflation and dark energy, can also be used to establish a systematic approach to inflationary reheating. We consider two methods. First, we…
In this letter we bring together the physics of preheating, following a period of inflation, and the dynamics of non-topological solitons, namely oscillons. We show that the oscillating condensate that makes up an oscillon can be an…
We study the inflationary model with a spectator scalar field $\chi$ coupled to both the inflaton and Ricci scalar. The interaction between the $\chi$ field and the gravity, denoted by $\xi R\chi^2$, can trigger the tachyonic instability of…
Small-field inflation (SFI) is widely considered to be unnatural because an extreme fine-tuning of the initial condition is necessary for sufficiently large e-folding. In this paper, we show that the unnaturally-looking initial condition…
A pseudoscalar inflaton $\varphi$, coupled to the topological charge density $F\tilde{F}$ of a non-Abelian sector, can decay to gauge bosons ($\varphi\to g g $), which may thermalize rapidly. The friction felt by $\varphi$ is then increased…
We study a model for reheating that has been much investigated for parametric resonance, having a quartic interaction of the scalar inflaton with another scalar field. Attention is particularly on the quantum excitations of the inflaton…
We consider the cosmological production of fermionic dark matter during inflation and a post-inflationary radiation dominated era. This fermion \emph{only interacts gravitationally}, has a mass $m$ much smaller than the Hubble scale during…
We propose a new mechanism to generate density perturbations in inflationary models. Spatial fluctuations in the decay rate of the inflaton field to ordinary matter lead to fluctuations in the reheating temperature. We argue that in most…
Inflationary magnetogenesis has long been assumed to be the most promising mechanism for producing large-scale magnetic fields in our universe. However, generically, such models are plagued with either backreaction or strong coupling…