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Related papers: New- vs. chaotic-inflations

200 papers

The previously proposed class of phenomenological inflationary models in which the assumption of inflaton slow-roll is replaced by the more general, constant-roll condition is compared with the most recent cosmological observational data,…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-28 Hayato Motohashi , Alexei A. Starobinsky

It is shown that a large class of higher-order (i.e. non-quadratic) scalar kinetic terms can, without the help of potential terms, drive an inflationary evolution starting from rather generic initial conditions. In many models, this…

High Energy Physics - Theory · Physics 2008-11-26 C. Armendariz-Picon , T. Damour , V. Mukhanov

The first year Wilkinson Microwave Anisotropy Probe data favors primordial adiabatic fluctuation with a running spectral index with $\ns >1$ on a large scale and $\ns <1$ on a smaller scale. The model building of inflation that predicts…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Kawasaki , Masahide Yamaguchi , Jun'ichi Yokoyama

We comprehensively explore the quadratic curvaton models in the chaotic inflation. In the light of the BICEP2 result $r \approx 0.2$, all model parameters and relevant observables are computed. It is found the curvaton field value is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Tomohiro Fujita , Masahiro Kawasaki , Shuichiro Yokoyama

We calculate the running of the scalar index in the ekpyrotic and matter bounce cosmological scenarios, and find that it is typically negative for ekpyrotic models, while it is typically positive for realizations of the matter bounce where…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-21 Jean-Luc Lehners , Edward Wilson-Ewing

We consider the running of the spectral index as a probe of both inflation itself, and of the overall evolution of the very early universe. Surveying a collection of simple single field inflationary models, we confirm that the magnitude of…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Peter Adshead , Richard Easther , Jonathan Pritchard , Abraham Loeb

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…

High Energy Physics - Phenomenology · Physics 2015-06-12 Keisuke Harigaya , Masahiro Ibe , Kai Schmitz , Tsutomu T. Yanagida

By writing the running of the scalar spectral index completely in terms of the scalar index $n_s$ and the tensor-to-scalar ratio $r$ we are able to impose constraints to models of inflation which are independent of the parameters of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-05 Gabriel German

Chain inflation is an alternative to slow-roll inflation in which the inflaton tunnels along a large number of consecutive minima in its potential. In this work we perform the first comprehensive calculation of the gravitational wave…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-09 Katherine Freese , Aliki Litsa , Martin Wolfgang Winkler

We provide a comprehensive numerical study of the Emergent Cyclic Inflation scenario. This is a scenario where instead of traditional monotonic slow roll inflation, the universe expands over numerous short asymmetric cycles due to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 William Duhe , Tirthabir Biswas

Primordial spectral indices are calculated to second order in slow-roll parameters for three closely-related models of inflation, all of which contain a scalar field non-minimally coupled to the Ricci curvature scalar. In most cases, $n_s$…

Astrophysics · Physics 2010-11-01 David Kaiser

A reformulation of inflationary model analyses appeared recently, in which inflationary observables are determined by the structure of a pole in the inflaton kinetic term rather than the shape of the inflaton potential. We comprehensively…

High Energy Physics - Theory · Physics 2016-08-04 Takahiro Terada

We consider the non-supersymmetric models of chaotic (driven by a quadratic potential) and hybrid inflation, taking into account the minimal possible radiative corrections to the inflationary potential. We show that two simple coupling…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 C. Pallis

We discuss a new test of inflation from the harmonic pattern of peaks in the cosmic microwave background radiation angular power spectrum. By characterizing the features of alternate models and revealing signatures essentially unique to…

Astrophysics · Physics 2009-08-18 Wayne Hu , Martin White

The model of fresh inflation with increasing cosmological parameter provides sufficient e-folds to solve the flatness/horizon problem and the density fluctuations agree with experimental values. In this model the temperature increases…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mauricio Bellini

It is pointed out that hybrid inflation can be implemented with the inflaton field rolling away from the origin instead of towards it. This `inverted' hybrid inflation has a spectral index $ n < 1 $, in contrast with ordinary hybrid…

High Energy Physics - Phenomenology · Physics 2008-11-26 David H. Lyth , Ewan D. Stewart

We develop a cosmological model where primordial inflation is driven by a 'solid', defined as a system of three derivatively coupled scalar fields obeying certain symmetries and spontaneously breaking a certain subgroup of these. The…

High Energy Physics - Theory · Physics 2015-06-11 Solomon Endlich , Alberto Nicolis , Junpu Wang

We study chaotic inflation with a quadratic potential in all dimensions. The spectral indices of scalar and tensor perturbations and also their running have been calculated in all dimensions.

Astrophysics · Physics 2008-11-26 Forough Nasseri

We introduce a new class of models of chaotic inflation inspired by the superconformal approach to supergravity. This class of models allows a functional freedom of choice of the inflaton potential V = |f(\phi)|^2. The simplest model of…

High Energy Physics - Theory · Physics 2010-11-22 Renata Kallosh , Andrei Linde

We show that generically the tensor-to-scalar ratio in large single-field inflation scenarios is bounded to be larger than $\mathcal{O}(10^{-3})$ for the spectral index in the range favored by observations.

Cosmology and Nongalactic Astrophysics · Physics 2015-09-25 Gabriela Barenboim , Wan-Il Park