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Related papers: Final Thoughts on the Power Spectra of Scalar Pote…

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We study the dynamics and predictions of a new emergent-universe model recently derived within Quantum Reduced Loop Gravity and based on the so-called statistical regularization scheme. These effective geometries show a dynamical transition…

General Relativity and Quantum Cosmology · Physics 2019-04-24 Javier Olmedo , Emanuele Alesci

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

We study inflationary models with a Gauss-Bonnet term to reconstruct the scalar field potentials and the Gauss-Bonnet coupling functions from the observable quantities. Using the observationally favored relations for both $n_s$ and $r$, we…

General Relativity and Quantum Cosmology · Physics 2017-06-14 Seoktae Koh , Bum-Hoon Lee , Gansukh Tumurtushaa

Recent observations suggest that the spectral index of the primordial perturbations is very close to unity, as expected in models of slow roll inflation. It is still possible for such models to produce spectra which are scale dependent. We…

Astrophysics · Physics 2009-09-02 Scott Dodelson , Ewan Stewart

Inflationary models predicting a scale-dependent large amplification of the density perturbations have recently attracted a lot of attention because the amplified perturbations can seed a sizable amount of primordial black holes (PBHs) and…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-28 Keisuke Inomata , Matteo Braglia , Xingang Chen , Sébastien Renaux-Petel

In inflationary cosmology, the form of the potential is still an open problem. In this work, second-order effects of the inflationary potential are evaluated and related to the known formula for the primordial perturbations at a wide range…

General Relativity and Quantum Cosmology · Physics 2024-11-01 Paulo Custodio , Cristian R. Ghezzi , Nadja S. Magalhae , Carlos Frajuca

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

We present a new approximation scheme that allows us to increase the accuracy of analytical predictions of the power spectra of inflationary perturbations for two specific classes of inflationary models. Among these models are chaotic…

Astrophysics · Physics 2015-06-24 C. A. Terrero-Escalante , D. J. Schwarz , A. A. Garcia

We discuss the possibility that we could obtain some hints of the heavy physics during inflation by analyzing local features of the primordial bispectrum. A heavy scalar field could leave large signatures in the primordial spectra through…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 Ryo Saito , Yu-ichi Takamizu

We study the implications of deformed quantum algebras for the generation of primordial perturbations from slow-roll inflation. Specifically, we assume that the quantum commutator of the inflaton's amplitude and momentum in Fourier space…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Andrew C. Day , Iain A. Brown , Sanjeev S. Seahra

There exist several theoretical motivations for primordial correlation functions (such as the power spectrum) to contain oscillations as a logarithmic function of comoving momentum k. While these features are commonly searched for in…

High Energy Physics - Theory · Physics 2014-01-22 Mark G. Jackson , Ben Wandelt , François Bouchet

This article examines how a breakdown of a locally Lorentz invariant, point-like description of nature at tiny space-time intervals would translate into a distinctive set of signals in the primordial power spectrum generated by inflation.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hael Collins , R. Holman

We show how observations of the density perturbation (scalar) spectrum and the gravitational wave (tensor) spectrum allow a reconstruction of the potential responsible for cosmological inflation. A complete functional reconstruction or a…

High Energy Physics - Phenomenology · Physics 2009-10-22 Edmund J. Copeland , Edward W. Kolb , Andrew R. Liddle , James E. Lidsey

Emergent cosmological models, together with the Big Bang and bouncing scenarios, are among the possible descriptions of the early Universe. This work aims at clarifying some general features of the primordial tensor power spectrum in this…

General Relativity and Quantum Cosmology · Physics 2018-12-14 Killian Martineau , Aurélien Barrau

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

This paper discusses the use of absolutely one-homogeneous regularization functionals in a variational, scale space, and inverse scale space setting to define a nonlinear spectral decomposition of input data. We present several theoretical…

Numerical Analysis · Computer Science 2016-01-13 Martin Burger , Guy Gilboa , Michael Moeller , Lina Eckardt , Daniel Cremers

We calculate power spectra of cosmological perturbations at high accuracy for two classes of inflation models. We classify the models according to the behaviour of the Hubble distance during inflation. Our approximation works if the Hubble…

Astrophysics · Physics 2009-11-06 Dominik J. Schwarz , Cesar A. Terrero-Escalante , Alberto A. Garcia

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 expound ten principles in an attempt to clarify the debate over infrared loop corrections to the primordial scalar and tensor power spectra from inflation. Among other things we note that existing proposals for nonlinear extensions of…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-04 S. P. Miao , R. P. Woodard

We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different with respect to the usual power-law, arising from the simplest models of cosmological inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 Stefano Gariazzo