Related papers: Inflation and Preheating in Supergravity with MSSM…
We study a recently proposed running kinetic inflation model in which the inflaton potential becomes flat due to rapid growth of the kinetic term at large inflaton field values. As concrete examples, we build a variety of chaotic inflation…
Supergravity is a well-motivated theory beyond the standard model of particle physics, and a suitable arena to study high-energy physics at the early universe including inflation, whose observational evidences are growing more and more.…
We consider the generation of large-scale magnetic fields in slow-roll inflation. The inflaton field is described in a supergravity framework where the conformal invariance of the electromagnetic field is generically and naturally broken.…
The inflation within the MSSM is proposed, where the inflaton field is a combination of the Higgs, squark and slepton states. While the inflationary phase is fully governed by the electron Yukawa superpotential coupling, the fields'…
We explore a new class of supersymmetric models of inflation where the inflaton is realised as a combination of a Higgs field and (gauge non-singlet) matter fields, using a "tribrid" structure of the superpotential. Inflation is associated…
We describe the primeval inflationary phase of the early Universe within a quantum field theoretical (QFT) framework that can be viewed as the effective action of vacuum decay in the early times. Interestingly enough, the model accounts for…
We propose a class of inflation models in which the coefficient of the inflaton kinetic term rapidly changes with energy scale. This may occur especially if the inflaton moves over a long distance during inflation as in the case of…
We present a two stage hybrid inflationary scenario in non-minimal supergravity which can predict values of the tensor-to-scalar ratio of the order of few times 0.01. For the parameters considered, the underlying supersymmetric particle…
Inflation is the currently accepted paradigm for the beginnings of the Universe. To explain the observed almost scale invariant spectrum of density perturbations with only a slight spectral tilt, inflation must have been "slow roll", that…
We study the possibility that inflation is driven by a scalar field together with a vector field minimally coupled to gravity. By assuming an effective potential that incorporates both fields into the action, we explore two distinct…
The temperature fluctuations in the cosmic microwave background observed by COBE provide strong support for an inflationary phase in the early universe, below the GUT scale. We argue that a singlet field in a hidden sector of an effective…
This paper provides a systematic study of supergravity contributions relevant for inflationary model building in Jordan frame supergravity. In this framework, canonical kinetic terms in the Jordan frame result in the separation of the…
There are many flat directions in SUSY models, which may dissipate their energy and source the radiation background during inflation. However, the only possibility that has been studied in this direction is warm inflation, which uses "warm"…
We look at the possibility of non-perturbative particle production after inflation from SUSY flat directions produced by rotating eigenstates thereby avoiding the standard adiabaticity conditions. This might lead to preheating and prevent…
Recent work is reported on inflation model building in the context of supergravity and superstrings, with special emphasis on False Vacuum (`Hybrid') Chaotic Inflation. Globally supersymmetric models do not survive in generic supergravity…
We present a superconformal master action for a class of supergravity models with one arbitrary function defining the Jordan frame. It leads to a gauge-invariant action for a real vector multiplet, which upon gauge fixing describes a…
Motivated by our earlier paper \cite{am}, we discuss how the infamous gravitino problem has a natural built in solution within supersymmetry. Supersymmetry allows a large number of flat directions made up of {\it gauge invariant}…
Adopting a recently proposed single-superfield framework of supergravity inflation, we consider large field inflationary models in which MSSM Higgs-like fields play the role of the inflaton. In the simplest cases, the inflaton potential has…
One of the great triumphs of the inflationary model is the prediction of the flat power spectrum of the CMB fluctuation. The prediction is based on the assumption of the de-Sitter vacuum in the past infinity. However, the true past infinity…
It is shown that in a smooth hybrid inflation model in supergravity adiabatic fluctuations with a running spectral index with $\ns >1$ on a large scale and $\ns <1$ on a smaller scale can be naturally generated, as favored by the first-year…