Related papers: Inflation from a chaotic potential with a step
A bidimensional parameter space of unitary area is introduced to study phenomenologically the dynamic and thermodynamic behavior of inflationary models driven by a scalar field coupled to a thermal component. In this enlarged context the…
In the present work we study the consequences of considering a new family of single-field inflation models, called power-law plateau inflation, in the warm inflation framework. We consider the inflationary expansion is driven by a standard…
We study chaotic inflation driven by a real, massive, homogeneous minimally coupled scalar field in a flat Robertson-Walker spacetime. The semiclassical limit for gravity is considered, whereas the scalar field is treated quantum…
We consider the spectrum of primordial fluctuations produced by inflationary models where the inflaton potential is the sum of two exponential terms. A wide range of spectra result, with the only constraint being that the scalar spectrum…
We present a perturbative approach for studying inflation models with soft departures from scale free spectra of the power law model. In the perturbed power law (PPL) approach one obtains at the leading order both the scalar and tensor…
In the present work we study a warm inflationary model defined by a quasi-exponential inflaton potential and an inflaton decay rate proportional to the Hubble rate. The model is characterized by three free parameters. We compute the power…
We consider trapped inflation in a higher dimensional field space: particle production at a dense distribution of extra species points leads to a terminal velocity at which inflation can be driven in steep potentials. We compute an…
Non-commutativity of spacetime at the Planck scale may deform the usual dispersion relations. And these deformed dispersion relations could lead to the accelerating phase without a scalar field. In this paper, we have calculated the…
The Reheating era of inflationary universe can be parameterized by various parameters like reheating temperature \(T_{\text{re}}\), reheating duration \(N_{\text{re}}\) and average equation of state parameter \(\overline{\omega…
The CMB power spectra are studied for different families of single field new and chaotic inflation models in the effective field theory approach to inflation. We implement a systematic expansion in 1/N_e where N_e ~ 50 is the number of…
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 study quintessential inflation with an inverse hyperbolic type potential $V(\phi) = {V_0}/{\cosh \left( {\phi^n}/{\lambda^n} \right)}$, where $V_0$, $\lambda$ and "n" are parameters of the theory. We obtain a bound on $\lambda$ for…
We investigate the cosmological perturbation theory and calculate the perturbation spectra in the warm $k$-inflation. Unlike the scalar perturbations of $k$-inflation in the cold inflationary scenario, entropy perturbations should be…
Some of the consequences for inflationary cosmology of a scale dependence (running) in the tilt of the scalar perturbation spectrum are considered. In the limit where the running is itself approximately scale-invariant, a relationship is…
Models of chaotic inflation with a fractional power-law potential are not only viable but also testable in the foreseeable future. We show that such models can be realized in simple strongly coupled supersymmetric gauge theories. In these…
The latest results from PLANCK impose strong constraints on features in the spectrum of the curvature perturbations from inflation. We analyse the possibility of particle production induced by sharp turns of the trajectory in field space in…
We argue that in models of inflation with two scalar fields and non-canonical kinetic terms there is a possibility of obtaining a red tilt of the power spectrum of curvature perturbations from noncanonicality-induced interactions between…
Nonminimally coupled inflation models based on a nonminimal coupling $\xi \phi^{2} R$ and a $\phi^{4}$ potential are in excellent agreement with the scalar spectral index observed by Planck. Here we consider the modification of these models…
The effect of the initial conditions in inflation on scalar and tensor perturbations is investigated. Formulae for the power spectra of gravitational waves and curvature perturbations for any initial conditions in inflation are derived, and…
We carry out numerical investigations of the dynamics and perturbations in the Nflation model of Dimopoulos et al. (2005). This model features large numbers of scalar fields with different masses, which can cooperate to drive inflation…