English
Related papers

Related papers: Toward inflation models compatible with the no-bou…

200 papers

The inflationary scenario is not the only paradigm of early universe cosmology which is consistent with current observations. General criteria will be presented which any successful early universe model must satisfy. Various ways, including…

High Energy Physics - Theory · Physics 2018-09-14 Robert H. Brandenberger

The no-boundary wave function of quantum gravity usually assigns only very small probability to long periods of inflation. This was a reason to doubt about the no-boundary wave function to explain the observational universe. We study the…

General Relativity and Quantum Cosmology · Physics 2013-10-09 Dong-il Hwang , Soo A Kim , Bum-Hoon Lee , Hanno Sahlmann , Dong-han Yeom

We analyse models of inflation in which isocurvature perturbations present during inflation are converted into the primordial curvature perturbation during instant preheating. This can be due to an asymmetry between the fields present…

Astrophysics · Physics 2014-11-18 Christian T. Byrnes

We study `hilltop' inflation, in which inflation takes place near a maximum of the potential. Viewed as a model of inflation after the observable Universe leaves the horizon (observable inflation) hilltop inflation is rather generic. If the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Lotfi Boubekeur , David. H. Lyth

We explore the consequences of a detection of primordial tensor fluctuations for general single-field models of inflation. Using the effective theory of inflation, we propose a generalization of the Lyth bound. Our bound applies to all…

High Energy Physics - Theory · Physics 2015-06-03 Daniel Baumann , Daniel Green

We investigate the observational signatures of many-field inflation and present analytic expressions for the spectral index as a function of the prior. For a given prior we employ the central limit theorem and the horizon crossing…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Perseas Christodoulidis , Diederik Roest , Robert Rosati

A unified approach to quintessence and inflation is investigated with the use of a single scalar field. It is argued that successful potentials have to approximate a combination of exponential and inverse power-law decline in the limit of…

Astrophysics · Physics 2007-05-23 Konstantinos Dimopoulos

Small-field inflation typically requires rather special initial conditions to commence. It is proposed that in models where the inflaton is an axionlike field, with a periodic contribution to the potential, there is a possibility of…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-05 Michal Spalinski

We are on the verge of the first precision testing of the inflationary cosmology as a model for the origin of structure in the Universe. I review the key predictions of inflation which can be used as observational tests, in the sense of…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

If a coupling between the inflaton and the Gauss-Bonnet term is introduced, many models of inflation that were ruled out by the most recent Planck data can be made viable again. The predictions for the scalar spectral index and…

General Relativity and Quantum Cosmology · Physics 2025-04-22 Kamil Mudrunka , Kazunori Nakayama

We review models which generate a large non-Gaussianity of the local form. We first briefly consider three models which generate the non-Gaussianity either at or after the end of inflation; the curvaton scenario, modulated (p)reheating and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Christian T. Byrnes , Ki-Young Choi

We compute analytic expressions for the non-linearity parameters characterizing the bi- and tri-spectrum of primordial curvature perturbations generated during an inflationary epoch of the early universe driven by an arbitrary number of…

High Energy Physics - Theory · Physics 2011-11-04 Diana Battefeld , Thorsten Battefeld

The early Universe inflation is well known as a promising theory to explain the origin of large scale structure of Universe and to solve the early universe pressing problems. For a resonable inflation model, the potential during inflation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xin He Meng

Recently, a model of inflation using non-minimally coupled massive vector fields has been proposed. For a particular choice of non-minimal coupling parameter and for a flat FRW model, the model is reduced to the model of chaotic inflation…

General Relativity and Quantum Cosmology · Physics 2014-11-18 Takeshi Chiba

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,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Lisa Randall , Marin Soljacic , Alan Guth

We revisit arguments that simple models of inflation with a small red tilt in the scalar power spectrum generically yield an observable tensor spectrum. We show that criteria for fine-tuning based upon the algebraic simplicity of the…

Astrophysics · Physics 2008-12-18 Simeon Bird , Hiranya V. Peiris , Richard Easther

A scenario with two subsequent periods of inflationary expansion in the very early universe is examined. The model is based on a potential motivated by symmetries being found in field theory at high energy. For various parameter sets of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Simon Schettler , Jurgen Schaffner-Bielich

We present the first calculation of the Bayesian evidence for different prototypical single field inflationary scenarios, including representative classes of small field and large field models. This approach allows us to compare…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-10 Jerome Martin , Christophe Ringeval , Roberto Trotta

There has been much recent discussion, and some confusion, regarding the use of existing observational data to estimate the likelihood that next-generation cosmic microwave background (CMB) polarization experiments might detect a nonzero…

Astrophysics · Physics 2024-03-13 Wessel Valkenburg , Lawrence M. Krauss , Jan Hamann

We study a supergravity model of inflation essentially depending on one parameter which can be identified with the slope of the potential at the origin. In this type of models the inflaton rolls at high energy from negative values and a…

Astrophysics · Physics 2009-11-10 G. German , A. de la Macorra