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Related papers: Cosmological Perturbations without Inflation

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Following a self-contained review of the basics of the theory of cosmological perturbations, we discuss why the conclusions reached in the recent paper by Kaloper et al are too pessimistic estimates of the amplitude of possible imprints of…

High Energy Physics - Theory · Physics 2016-09-06 Robert H. Brandenberger , Jerome Martin

Recent measurements by the {\it Planck} experiment of the power spectrum of temperature anisotropies in the cosmic microwave background radiation (CMB) reveal a deficit of power in low multipoles compared to the predictions from best-fit…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-19 Katelin Schutz , Evangelos I. Sfakianakis , David I. Kaiser

Though predictions of the simplest inflationary cosmological models with cold dark matter, flat space and approximately flat initial spectrum of adiabatic perturbations are remarkably close to observational data, we have to go beyond them…

Astrophysics · Physics 2011-04-15 A. A. Starobinsky

A recent paper argued that it is not possible to infer the energy scale of inflation from the amplitude of tensor fluctuations in the Cosmic Microwave Background, because the usual connection is substantially altered if there are a large…

High Energy Physics - Theory · Physics 2016-01-20 Matthew Kleban , Mehrdad Mirbabayi , Massimo Porrati

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ralf Hofmann , Mathias Th. Keil

We analyze the limits on resonant particle production during inflation based upon the power spectrum of fluctuations in matter and the cosmic microwave background. We show that such a model is consistent with features observed in the matter…

Astrophysics · Physics 2009-11-10 G. J. Mathews , D. J. H. Chung , K. Ichiki , T. Kajino , M. Orito

We consider the non-commutative inflation model of [3] in which it is the unconventional dispersion relation for regular radiation which drives the accelerated expansion of space. In this model, we study the evolution of linear cosmological…

High Energy Physics - Theory · Physics 2008-11-26 Seoktae Koh , Robert H. Brandenberger

In the first part of this paper, we outline the construction of an inflationary cosmology in the framework where inflation is described by a universally evolving scalar field, with the Lagrangian ${\cal L}_\phi=-{1/2}(\partial\phi)^2…

Astrophysics · Physics 2009-12-15 Ishwaree P. Neupane , Christoph Scherer

It is possible that the expansion of the universe began with an inflationary phase, in which the inflaton driving the process also was a Higgs field capable of stabilizing magnetic monopoles in a grand-unified gauge theory. If so, then the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alfred Scharff Goldhaber

The isotropy and homogeneity of the cosmic microwave background (CMB) favors "scalar driven" early Universe inflationary models. Non-scalar fields, and in particular gauge fields, are on the other hand commonplace in all high energy…

High Energy Physics - Theory · Physics 2015-06-12 A. Maleknejad , M. M. Sheikh-Jabbari , J. Soda

We show that the presence of a temporal electromagnetic field on cosmological scales generates an effective cosmological constant which can account for the accelerated expansion of the universe. Primordial electromagnetic quantum…

Astrophysics · Physics 2011-07-13 Jose Beltran Jimenez , Antonio L. Maroto

In the framework of the Connes-Lott model based on noncommutative geometry, the basic features of a gauge theory in the presence of gravity are reviewed, in order to show the possible physical relevance of this scheme for inflationary…

General Relativity and Quantum Cosmology · Physics 2009-10-28 F. Lizzi , G. Mangano , G. Miele , G. Sparano

We study inflation in a recently proposed gravitational effective field theory describing the trace anomaly. The theory requires an additional scalar which is massless in the early universe. This scalar -- referenced as an anomalyon --…

High Energy Physics - Theory · Physics 2025-03-17 Gregory Gabadadze , David N. Spergel , Giorgi Tukhashvili

I review the general aspects of cosmological parameter estimation from observations of the cosmic microwave background (CMB) temperature anisotropies in the framework of inflationary adiabatic models. The most recent CMB datasets are…

Astrophysics · Physics 2009-10-31 A. Balbi

The existence of large-scale anisotropy can not be ruled out by the cosmic microwave background (CMB) radiation. Over the years, several models have been proposed in the context of anisotropic inflation to account for CMB's cold spot and…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-15 Sourav Pal , Debaprasad Maity , Tuan Q. Do

For simple inflationary models, we provide a consistent and complete scheme by which the macro-physical details of early universe inflation may be determined explicitly from the underlying micro-physical theory. We examine inflationary…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Cormier

The existence of the inflationary era in the early Universe seems to be strongly supported by recent CMB observations. However, only a few realistic inflation scenarios which have close relation to particle physics seem to have been known…

High Energy Physics - Phenomenology · Physics 2015-01-05 Romy H. S. Budhi , Shoichi Kashiwase , Daijiro Suematsu

We compute the rate with which super-Hubble cosmological fluctuations are decohered during inflation, by their gravitational interactions with unobserved shorter-wavelength scalar and tensor modes. We do so using Open Effective Field Theory…

High Energy Physics - Theory · Physics 2023-07-12 C. P. Burgess , R. Holman , Greg Kaplanek , Jerome Martin , Vincent Vennin

How well can we constrain the initial quantum state of metric perturbations sourced during inflation? We exhibit an interesting new class of quantum states that entangle the scalar metric perturbations {\zeta} with other fields such as…

High Energy Physics - Theory · Physics 2018-06-04 Andreas Albrecht , Nadia Bolis , R. Holman