Related papers: Adiabatic Media Inflation
We assay how inflationary models whose properties are dominated by the dynamics of a single scalar field are constrained by cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP). We classify…
We study cosmological dynamics of the energy-momentum squared gravity. By adding the squared of the matter field's energy-momentum tensor ($\zeta\, \textbf{T}^{2}$) to the Einstein Hilbert action, we obtain the Einstein's field equations…
It is conjectured that inflation, taking account of quantum gravity, leads to a discrete spectrum of cosmological perturbations, instead of the continuous Gaussian spectrum predicted by standard field theory in an unquantized background.…
We employ the effective field theory approach for multi-field inflation which is a generalization of Weinberg's work. In this method the first correction terms in addition to standard terms in the Lagrangian have been considered. These…
With an energy scale that can be as high as $10^{14}\,{\rm GeV}$, inflation may provide a unique probe of high-energy physics. Both scalar and tensor fluctuations generated during this early accelerated expansion contain crucial information…
The conventional slow-roll approximation is broken in the so-called "ultra slow-roll" models of inflation, for which the inflaton potential is exactly (or extremely) flat. The interesting nature of (canonical) ultra slow-roll inflation is…
We introduce a new method for calculating density perturbations in hybrid inflation which avoids treating the fluctuations of the "waterfall" field as if they were small perturbations about a classical trajectory. We quantize only the…
We consider the space-condensate inflation model to study the primordial gravitational waves generated in the early Universe. We calculate the energy spectrum of gravitational waves induced by the space-condensate inflation model for full…
We derive the implications for anisotropies in the cosmic microwave background following from a model of inflation in which a bare cosmological constant is gradually screened by an infrared process in quantum gravity. The model predicts…
We perform adiabatic regularization of power spectrum in nonminimally coupled general single-field inflation with varying speed of sound. The subtraction is performed within the framework of earlier study by Urakawa and Starobinsky dealing…
Motivated by the reported discovery of inflationary gravity waves by the BICEP2 experiment, we propose an inflationary scenario in supergravity, based on the standard superpotential used in hybrid inflation. The new model yields a…
We study non-linear primordial adiabatic and isocurvature perturbations and their non-Gaussianity. After giving a general formulation in the context of an extended delta N-formalism, we analyse in detail two illustrative examples. The first…
We propose a new version of the hybrid inflation scenario that produces a significantly tilted n>1 spectrum of curvature perturbations. This may happen in supersymmetric models where the inflaton field acquires a mass proportional to the…
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…
We provide some comments about the constraints on the inflationary models inferred from the two Swampland criteria which have been recently proposed. In particular we argue that, in the absence of any knowledge about the origin of the…
Perfect fluids are modeled by using an effective field theory approach which naturally gives a self-consistent and unambiguous description of the intrinsic non-adiabatic contribution to pressure variations. We study the impact of intrinsic…
Inflationary cosmology provides a natural mechanism for the generation of primordial perturbations which seed the formation of observed cosmic structure and lead to specific signals of anisotropy in the cosmic microwave background…
We study the non-gaussianity from the bispectrum in multi-field inflation models with a general kinetic term. The models include the multi-field K-inflation and the multi-field Dirac-Born-Infeld (DBI) inflation as special cases. We find…
This study presents a computational and theoretical framework inspired by thermodynamic principles to analyze the dynamics of economic inflation within adiabatic and non-adiabatic systems. In a framework referred to as developmental…
The precision reached by the recent CMB measurements gives new insights into the shape of the primordial power spectra of the cosmological perturbations. In the context of inflationary cosmology, this implies that the CMB data are now…