Related papers: Exponential potential for an inflaton with nonmini…
We consider cosmological inflation generated by a scalar field slowly rolling off from a de Sitter maximum of its potential. The models belong to the class of hilltop models and represent the most general model of this kind in which the…
We show that if the inflaton has a non-minimal coupling to gravity and the Planck scale is dynamically generated, the results of Coleman-Weinberg inflation are confined in between two attractor solutions: quadratic inflation, which is ruled…
We focus on the inflationary predictions of $\beta$-exponential potential models, in which the inflaton is a representation of the field delineating the size of extra-dimension. Since it offers a well-motivated starting point for the study…
We have found a successful model of chaotic inflation with an inflaton coupled nonminimally with gravity. The nonminimal coupling constant $\xi$ runs with the evolution of the inflaton. The running nature of the coupling leads naturally to…
The possibility that the non-minimal coupling inflation could be eternal is investigated. We calculate the quantum fluctuation of the inflaton in a Hubble time and find that it has the same value as in the minimal case in the slow-roll…
We argue that double inflation may occur when a spectator field is non-minimally coupled to gravity. As a concrete example, we study a two-field inflationary model where the initial spectator field is non-minimally coupled to gravity while…
We propose an inflationary scenario where the inflaton field is non-minimally coupled to spacetime curvature and inflation is driven by a vacuum energy symmetry breaking potential without specifying \emph{a priori} whether the inflaton…
We investigate a standard minimally-coupled scalar-field inflationary scenario, which is based on a new potential, with suitably generalized plateau features, that leads to extra small tensor-to-scalar ratios. In particular, we consider a…
We investigate the non-Gaussianities of inflation driven by a single scalar field coupling non-minimally to the Einstein Gravity. We assume that the form of the scalar field is very general with an arbitrary sound speed. For convenience to…
Single field inflationary models are investigated within Palatini quadratic gravity represented by $R+\alpha R^2$ along with a non-minimal coupling of the form $f(\phi) R$ between the inflaton field $\phi$ and the gravity. The treatment is…
We present a unified framework that simultaneously addresses the dynamics of early-time cosmic inflation and late-time cosmic acceleration within the context of a single scalar field non-minimally coupled to gravity. By employing an…
We discuss the introduction of a non minimal coupling between the inflaton and gravity in terms of the recently proposed $\beta$-function formalism for inflation\cite{Binetruy:2014zya}. Via a field redefinition we reduce to the case of…
We investigate inflationary models in f(R,T) modified gravity with a kinetic coupling term \omega^2 G^{\mu\nu}\partial_{\mu}\phi\partial_{\nu}\phi having a positive factor needed to remove the ghosts. Taking f(R,T)=R+2\beta T, we calculate…
Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor…
We show explicitly how the T model, E model, and Hilltop inflations are obtained from the general scalar-tensor theory of gravity with arbitrary conformal factors in the strong coupling limit. We argue that $\xi$ attractors can give any…
We investigate the cosmological inflation in a class of supergravity models that are generalizations of non-supersymmetric $R^2$ models. Although such models have been extensively studied recently, especially after the launch of the PLANCK…
We study cosmological evolution after inflation in models with non-minimal derivative coupling to gravity. The background dynamics is solved and particle production associated with rapidly oscillating Hubble parameter is studied in detail.…
We study single-field slow-roll inflation embedded in Palatini $F(R)$ gravity where $F(R)$ grows faster than $R^2$. Surprisingly, the consistency of the theory requires the Jordan frame inflaton potential to be unbounded from below. Even…
One of the fundamental objectives of contemporary cosmology is to understand the physics of the inflationary universe, owing to its observably verifiable predictions about the very early universe with an energy scale of $\sim 10^{16}$ GeV.…
We investigate, in a model-independent way, the conditions required to obtain a satisfactory model of extended inflation in which inflation is brought to an end by a first-order phase transition. The constraints are that the correct present…