Related papers: Chromo-Natural inflation in Supergravity
We re-examine approximations in the analytical calculation of the primordial spectrum of cosmological perturbation produced during inflation. Taking two inflation models (chaotic inflation and natural inflation) as examples, we numerically…
A variant of hybrid inflation which is applicable in a wide class of supersymmetric grand unified models and reproduces the observed temperature perturbations of cosmic background radiation with natural values of the parameters is…
Two distinct classes of realistic inflationary models consistent with present observations are reviewed. The first example relies on the Coleman-Weinberg potential and is readily realized within the framework of spontaneously broken global…
We consider models of inflation in supergravity with a shift symmetry. We focus on models with one moduli and one inflaton field. The presence of this symmetry guarantees the existence of a flat direction for the inflaton field. Mildly…
We obtain a new class of exact cosmological solutions for multi-scalar fields with exponential potentials. We generalize the assisted inflation solutions previously obtained, and demonstrate how they are modified when there exist…
We study models of hybrid inflation in the framework of supergravity with superconformal matter. F-term hybrid inflation is not viable since the inflaton acquires a large tachyonic mass. On the contrary, D-term hybrid inflation can…
In this article we motivate and review the embedding of the gravitationally enhanced friction mechanism in supergravity. The very interesting feature is that inflationary models which utilize this mechanism drive inflation for a wider range…
Natural supergravity models of new inflation are reconsidered as minimal inflationary models within slow-roll approximation. Their running spectral index is derived in a revised form with recent observational results and future refinements…
We show that a particular class of effective low energy supergravity theories motivated by string theory can provide a promising framework for models of hybrid inflation in which the potential energy which drives inflation originates from…
We revisit the D-term inflation and amend it with ghost-free higher derivative couplings of chiral superfields to super-curvature. These couplings realize a more generic inflationary phase in supergravity. After pointing out that a…
The shift-symmetric coupling of a pseudo-scalar particle driving inflation to gauge fields provides a unique way of probing cosmic inflation. We show for an SU(2) gauge group how a classical isotropic background gauge field develops from…
Most models of inflation have small parameters, either to guarantee sufficient inflation or the correct magnitude of the density perturbations. In this paper we show that, in supersymmetric theories with weak scale supersymmetry breaking,…
We address an issue what kind of tuning realizes a flat potential for inflaton in supergravity. We restrict ourselves to the case that inflationary dynamics is not affected by separate supersymmetry-breaking effects, and consider examples…
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 comprehensively investigate a chaotic inflation model proposed recently in the framework of supergravity. In this model, the form of K\"ahler potential is determined by a symmetry, that is, the Nambu-Goldstone-like shift symmetry, which…
We study the initial value problem of new inflation models in the scheme of supergravity. We find that an inflaton generally acquires a mass of the order of the Hubble parameter via gravitationally suppressed interactions with particles in…
We propose a topological inflation model in the framework of supergravity with $R$ invariance. This topological inflation model is not only free from the initial value problem of the inflaton field but also gives low reheating temperature…
We extend the Cecotti-Kallosh model of Starobinsky inflation in supergravity by adding a holomorphic function to the superpotential in order to generate a large peak in the power spectrum of scalar (curvature) perturbations. In our…
Models of induced-gravity inflation are formulated within Supergravity employing as inflaton the Higgs field which leads to a spontaneous breaking of a U(1)B-L symmetry at Mgut=2x10^16 GeV. We use a renormalizable superpotential, fixed by a…
We propose a model of inflation in the framework of brane cosmology driven by background supergravity. Starting from bulk supergravity we construct the inflaton potential on the brane and employ it to investigate for the consequences to…