Related papers: Constraining the curvaton scenario
We explore the dynamics and observational predictions of the Warm Little Inflaton scenario, presently the simplest realization of warm inflation within a concrete quantum field theory construction. We consider three distinct types of scalar…
The spectral index is studied at the point where scalar fields deviate from slow-roll during inflation. Considering the deviation that may cause a significant difference to the time derivative of the Hubble parameter and also to the terms…
In this thesis we will primarily demonstrate how additional scalar degrees of freedom - which are motivated from many high-energy embeddings - open up new observational windows onto the physics of inflation. We construct a Bayesian…
The field responsible for the cosmological curvature perturbations generated during a stage of primordial inflation might be the ``curvaton'', a field different from the inflaton field. To keep the effective mass of the curvaton small…
Based on the renormalizable theory of gravitation recently proposed by Horava, we present a simple scenario to generate almost scale-invariant, super-horizon curvature perturbations. The anisotropic scaling with dynamical critical exponent…
We discuss a recently proposed scenario where the sparticle masses are purely mediated by gravity through the superconformal anomaly. This scenario elegantly evades the supersymmetric flavor problem since soft masses, like the anomaly, are…
We review the connection between inflationary models and observations and concentrate to describe models based on softly broken supersymmetry, in particular running mass models, and their predictions. We then present a fit of the spectral…
The inflaton necessary to implement the mechanism of inflationary cosmology has natural candidates in quiver gauge theory. We discuss the dimensionless coefficients of quartic couplings and enumerate scalars which are singlet under the…
We place functional constraints on the shape of the inflaton potential from the cosmic microwave background through a variant of the generalized slow roll approximation that allows large amplitude, rapidly changing deviations from…
Inflating curvaton can create curvature perturbation when the curvaton density is slowly varying. Using the delta-N formalism, we discuss the evolution of the curvature perturbation during curvaton inflation and find analytic formulation of…
The evolution of gauge invariant second-order scalar perturbations in a general single field inflationary scenario are presented. Different second order gauge invariant expressions for the curvature are considered. We evaluate…
We consider the potential problems due to the production of inflatinos and gravitinos after inflation. Inflationary models with a single scale set by the microwave background anisotropies have a low enough reheat temperature to avoid…
We explore the three-point amplitude of curvature perturbations in scenarios suggested by high-scale supersymmetry breaking in String Theory, where the inflaton is forced to climb a steep exponential potential. We can do it at the price of…
We investigate density perturbations in the chain inflation scenario, where the inflaton undergoes successive tunneling transitions along one field direction. First we show that when the bubble walls associated with such a phase transition…
In this paper, we consider a model of quintessential inflation based upon inverse hyperbolic potential. We employ curvaton mechanism for reheating which is more efficient than gravitational particle production; the mechanism complies with…
Cosmological perturbations, originating in the quantum fluctuations of the fields that drive inflation, are observed to be nearly scale invariant at the largest scales. At smaller scales, however, perturbations are not severely constrained…
We investigate the isocurvaton model, in which the isocurvature perturbation plays a role in suppressing the curvature perturbation, and large non-Gaussianity and gravitational waves can be produced with no isocurvature perturbation for…
Inflation occurring at energy densities less than (10$^{14}$ GeV)$^4$ produces tensor perturbations too small to be measured by cosmological surveys. However, we show that it is possible to probe low scale inflation by measuring the mass of…
For a single scalar field with unit sound speed minimally coupled to Einstein gravity, there are exactly three distinct cosmological solutions which produce a scale invariant spectrum of curvature perturbations in a dynamical attractor…
We show how we can implement chaotic inflation in the context of supergravity by conveniently selecting the functional form of a strong enough non-minimal coupling between the inflaton and the Ricci scalar curvature. The procedure can be…