English
Related papers

Related papers: On the power spectrum generated during inflation

200 papers

Power spectra always play an important role in the theory of inflation. In particular, the ability to reproduce the galaxy matter power spectrum and the CMB temperature angular power spectrum coefficients to high accuracy is often…

General Relativity and Quantum Cosmology · Physics 2019-11-01 Herbert W. Hamber , Lu Heng Sunny Yu

We consider small-field models which invoke the usual framework for the effective field theory, and large-field models which go beyond that. Present and future possibilities for discriminating between the models are assessed, on the…

Astrophysics · Physics 2015-06-24 Laila Alabidi , David Lyth

In addition to generating the appropriate perturbation power spectrum, an inflationary scenario must take into account the need for inflation to end subsequently. In the context of single-field inflation models where inflation ends by…

Astrophysics · Physics 2009-11-10 Michaël Malquarti , Samuel M. Leach , Andrew R. Liddle

The scale--independence of the primordial curvature perturbation suggests that it comes from the vacuum fluctuation during inflation of a light scalar field. This field may be the inflaton, or a different `curvaton' field. The observation…

High Energy Physics - Phenomenology · Physics 2007-05-23 David H. Lyth

The decrease of both the rolling speed of the inflaton and the sound speed of the curvature perturbations can amplify the curvature perturbations during inflation so as to generate a sizable amount of primordial black holes. In the…

General Relativity and Quantum Cosmology · Physics 2024-01-17 Rongrong Zhai , Hongwei Yu , Puxun Wu

There exist several models of inflation that produce primordial bispectra that contain a large number of oscillations. In this paper we discuss these models, and aim at finding a method of detecting such bispectra in the data. We explain…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Daniel Meerburg

The large enhancement of the primordial power spectrum of the curvature perturbation can seed the formation of primordial black hole, that can play as a dark matter component in the Universe. In multi-filed inflation models, the curved…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-05 Ki-Young Choi , Su-beom Kang , Rathul Nath Raveendran

We develop methods to calculate the curvature power spectrum in models where features in the inflaton potential nonlinearly excite modes and generate high frequency features in the spectrum. The first nontrivial effect of excitations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Wayne Hu , Chen He , Hayato Motohashi

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…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Seoktae Koh , Bum-Hoon Lee , Gansukh Tumurtushaa

We study single-field inflationary models with steep step-like features in the potential that lead to the temporary violation of the slow-roll conditions during the evolution of the inflaton. These features enhance the power spectrum of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-18 I. Dalianis , G. P. Kodaxis , I. D. Stamou , N. Tetradis , A. Tsigkas-Kouvelis

The effect of the initial conditions in inflation on scalar and tensor perturbations is investigated. Formulae for the power spectra of gravitational waves and curvature perturbations for any initial conditions in inflation are derived, and…

High Energy Physics - Theory · Physics 2007-05-23 Shiro Hirai

We investigate the formation of large peaks in the inflationary curvature power spectrum from double-well potentials. In such scenarios, the initial CMB spectrum is created at large field values. Subsequently, the inflaton will cross one of…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Alexandros Karam , Niko Koivunen , Eemeli Tomberg , Antonio Racioppi , Hardi Veermäe

The spectrum of curvature perturbation generated during inflation is studied in the case the inflation-driving scalar field (inflaton) $\phi$ crosses over its potential extremum. It is shown that the nondecaying mode of perturbation has a…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jun'ichi Yokoyama , Shogo Inoue

We study the generation of a large power spectrum, necessary for primordial black hole formation, within the effective theory of single-field inflation. The mechanisms we consider include a transition into a ghost-inflation-like phase and…

High Energy Physics - Theory · Physics 2022-02-02 Guillermo Ballesteros , Sebastián Céspedes , Luca Santoni

Inflation offers a simple model for very early evolution of our Universe and the origin of primordial perturbations on large scales. Over the last 25 years we have become familiar with the predictions of single-field models, but inflation…

Astrophysics · Physics 2008-11-26 David Wands

We review why the search for a causal explanation of the large scale properties of the universe supports the idea that an extended period of accelerated expansion, called inflation, preceded primordial nucleosynthesis. As a consequence of…

Astrophysics · Physics 2011-01-28 Parentani Renaud

The main goal of this paper is to derive the primordial power spectrum for the scalar perturbations generated as a result of quantum fluctuations during an inflationary pe- riod by an alternative approach of field quantization[1-3].…

General Relativity and Quantum Cosmology · Physics 2012-02-23 M. Mohsenzadeh , A. Sojasi , E. Yusofi

A short introduction to structure formation is given, followed by a discussion of the possible characteristics of the initial perturbations assuming a generic inflationary origin. Observational data related to large-scale structure and the…

Astrophysics · Physics 2014-10-13 Pedro Viana

It is argued that the order of the analytic expressions for the calculation of the primordial perturbations from inflation exerts a strong influence upon the results of the analysis of observables dynamics based on these expressions and,…

Astrophysics · Physics 2007-05-23 C. A. Terrero-Escalante

We consider primordial fluctuations in thermal inflation scenario. Since the thermal inflation drives about 10 $e$-folds after the standard inflation, the time of horizon-exit during inflation corresponding to the present observational…

High Energy Physics - Theory · Physics 2010-02-18 Masahiro Kawasaki , Tomo Takahashi , Shuichiro Yokoyama