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Related papers: Non-linear inflationary perturbations

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We study nonlinear cosmological perturbations during the post-inflationary evolution, using the equivalence between a perfect barotropic fluid and a derivatively coupled scalar field with Lagrangian [-(\partial \phi)^2]^[(1+w)/2w]. Since…

Astrophysics · Physics 2009-11-13 Lotfi Boubekeur , Paolo Creminelli , Jorge Norena , Filippo Vernizzi

We present a general formalism that provides a systematic computation of the linear and non-linear perturbations for an arbitrary number of cosmological fluids in the early Universe going through various transitions, in particular the decay…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 David Langlois , Angela Lepidi

By making a suitable generalization of the Starobinsky stochastic inflation, we propose a classical phase space formulation of stochastic inflation which may be used for a quantitative study of decoherence of cosmological perturbations…

General Relativity and Quantum Cosmology · Physics 2012-01-04 Jan Weenink , Tomislav Prokopec

Preheating can convert superhorizon fluctuations of light scalar fields present at the end of inflation into observable density perturbations. We show in detail how lattice field theory simulations and the separate universes approximation…

Astrophysics · Physics 2008-09-30 Alex Chambers , Arttu Rajantie

We explore extensions of hybrid inflationary models in the context of supersymmetric D-term inflation. We point out that a large variety of inflationary scenarios can be encountered when the field content is extended. It is not only…

High Energy Physics - Phenomenology · Physics 2008-11-26 Francis Bernardeau , Tristan Brunier

We define fully non-perturbative generalizations of the uniform density and comoving curvature perturbations, which are known, in the linear theory, to be conserved on sufficiently large scales for adiabatic perturbations. Our non-linear…

Astrophysics · Physics 2009-11-10 David Langlois , Filippo Vernizzi

Primordial non-Gaussianities from multi-field inflation are a leading target for cosmological observations, because of the possible large correlations generated between long and short distances. These signatures are captured by the local…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-31 Dong-Gang Wang , Guilherme L. Pimentel , Ana Achúcarro

The full set of cosmological observables coming from linear scalar and tensor perturbations of loop quantum cosmology is computed in the presence of inverse-volume corrections. Background inflationary solutions are found at linear order in…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Martin Bojowald , Gianluca Calcagni

We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. Starting from the perturbed Einstein equations, we integrate out the non-relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ram Brustein , Antonio Riotto

We investigate non-Gaussianity in general multiple-field inflation using the formalism we developed in earlier papers. We use a perturbative expansion of the non-linear equations to calculate the three-point correlator of the curvature…

Astrophysics · Physics 2009-11-13 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

Inflation predicts that quantum fluctuations determine the large scale structure of the Universe. This raises the striking possibility that quantum mechanics, developed to describe nature at short distances, can be tested by studying nature…

General Relativity and Quantum Cosmology · Physics 2020-05-07 Julian Georg , Carl Rosenzweig

We consider a recent approach to the construction of gauge-invariant relational observables in gravity in the context of cosmological perturbation theory. These observables are constructed using a field-dependent coordinate system, which we…

General Relativity and Quantum Cosmology · Physics 2022-01-20 Markus B. Fröb , William C. C. Lima

In this paper we study some models where non-Abelian gauge vector fields endowed with a SU(2) group representation are the unique source of inflation and dark energy. These models were first introduced under the name of gaugeflation and…

General Relativity and Quantum Cosmology · Physics 2020-10-13 Alejandro Guarnizo , J. Bayron Orjuela-Quintana , César A. Valenzuela-Toledo

We explore whether multifield inflationary models make unambiguous predictions for fundamental cosmological observables. Focusing on $N$-quadratic inflation, we numerically evaluate the full perturbation equations for models with 2, 3, and…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-29 Richard Easther , Jonathan Frazer , Hiranya V. Peiris , Layne C. Price

We present an estimate for the non-linear parameter \tau_NL, which measures the non-gaussianity imprinted in the trispectrum of the comoving curvature perturbation, \zeta. Our estimate is valid throughout the inflationary era, until the…

Astrophysics · Physics 2010-10-27 David Seery , James E. Lidsey

We consider a cosmological model with non-Gaussian initial perturbations, which in principle could be generated in non-standard inflationary scenarios with two or more scalar fields. In particular we focus our attention on the model…

Astrophysics · Physics 2011-05-10 Dmitri Novikov , Jens Schmalzing , Viatcheslav F. Mukhanov

During inflation explicit perturbative computations of quantum field theories which contain massless, non-conformal fields exhibit secular effects that grow as powers of the logarithm of the inflationary scale factor. Starobinski\u{\i}'s…

Astrophysics · Physics 2009-11-10 R. P. Woodard

We study the bispectrum of the primordial curvature perturbation on uniform-density hypersurfaces generated by a kind of the noncanonical warm inflation, wherein the inflation is provided by a noncanonical scalar inflaton field that is…

General Relativity and Quantum Cosmology · Physics 2015-04-09 Xiao-Min Zhang , Jian-Yang Zhu

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-04 Joyce Byun , Rachel Bean

We consider non-canonical generalizations of two classes of simple single-field inflation models. First, we study the non-canonical version of "ultra-slow roll" inflation, which is a class of inflation models for which quantum modes do not…

Astrophysics · Physics 2009-11-13 Konstantinos Tzirakis , William H. Kinney
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