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Related papers: An Isocurvature CDM Cosmogony. I. A Worked Example…

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A companion paper presents a worked model for evolution through inflation to initial conditions for an isocurvature model for structure formation. It is shown here that the model is consistent with the available observational constraints…

Astrophysics · Physics 2009-10-30 P. J. E. Peebles

We discuss structure formation in models with a spectator field in small-field inflation which accommodate a secondary period of inflation. In such models, subgalactic scale primordial fluctuations can be much suppressed in comparison to…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Kari Enqvist , Till Sawala , Tomo Takahashi

We analyze constraints on parameters characterizing the pre-inflating universe in an open inflation model with a present slightly open $\Lambda$CDM universe. We employ an analytic model to show that for a broad class of inflation-generating…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-17 G. J. Mathews , I. -S. Suh , N. Q. Lan , T. Kajino

A setting constituted by $\mathbb{N}$ 3-form fields, without any direct interaction between them, minimally coupled to gravity, is introduced in this paper as a framework to study the early evolution of the universe. We focus particularly…

General Relativity and Quantum Cosmology · Physics 2014-07-04 K. Sravan Kumar , J. Marto , Nelson J. Nunes , Paulo Vargas Moniz

Causal seed models, such as cosmological defects, generically predict a distinctly different structure to the CMB power spectrum than inflation, due to the behavior of the perturbations outside the horizon. We provide a general analysis of…

Astrophysics · Physics 2009-08-18 Wayne Hu , David N. Spergel , Martin White

A brief account is given of large-scale structure modelling based on the assumption that the initial perturbations arise from inflation. A recap is made of the implications of inflation for large-scale structure; under the widely applicable…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

Recent developments in inflation model building, based on supersymmetry, have produced compelling models in which strings are produced at the end of inflation. In such models the cosmological perturbations are seeded both by the defects and…

Astrophysics · Physics 2009-10-31 Joao Magueijo , Carlo Contaldi , Mark Hindmarsh

Inflation, a period of exponential expansion in the early Universe, is considered an important part of the standard $\Lambda$CDM cosmological model, and plays a crucial role in explaining a wide range of current observations. The standard…

General Relativity and Quantum Cosmology · Physics 2023-12-08 Maria Pia Piccirilli , Gabriel Leon

In this paper we study the generation of primordial perturbations in a cosmological setting of bigravity during inflation. We consider a model of bigravity which can reproduce the $\Lambda$CDM background and large scale structure and a…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-02 Giulia Cusin , Ruth Durrer , Pietro Guarato , Mariele Motta

The evolution of a scalar field is explored taking into account the presence of a background fluid in a positively curved Universe in the framework of loop quantum cosmology. Though the mechanism that provides the initial conditions for…

Astrophysics · Physics 2009-11-13 N. J. Nunes

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 study the evolution of the curvature perturbation on the super-horizon scales starting from the inflationary epoch until there remains only a single dynamical degree of freedom, presureless matter, in the universe. We consider the cosmic…

High Energy Physics - Phenomenology · Physics 2009-03-27 Ki-Young Choi , Jinn-Ouk Gong , Donghui Jeong

Inflationary models involving more than one scalar field naturally produce isocurvature perturbations. However, while these are fairly well studied, less is known about their evolution through the reheating epoch, when the inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Ian Huston , Adam J. Christopherson

In this work we investigate the behavior of three-dimensional (3D) cosmological models. The simulation of inflationary and dark-energy-dominated eras are among the possible results in these 3D formulations; taking as starting point the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. H. Christmann , F. P. Devecchi , G. M. Kremer , C. M. Zanetti

We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $\Phi_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed…

High Energy Physics - Theory · Physics 2010-10-13 Amjad Ashoorioon , Hassan Firouzjahi , M. M. Sheikh-Jabbari

It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological…

General Physics · Physics 2009-11-13 Jose Beltran Jimenez , Tomi S. Koivisto , Antonio L. Maroto , David F. Mota

In these lectures I review the standard hot big-bang cosmology, emphasizing its successes, its shortcomings, and its major challenge---a detailed understanding of the formation of structure in the Universe. I then discuss the motivations…

Astrophysics · Physics 2007-05-23 Michael S. Turner

Perhaps the deepest mystery of our accelerating Universe in expansion is the existence of a tiny and rigid cosmological constant, $\Lambda$. Its size is many orders of magnitude below the expected one in the standard model of particle…

General Relativity and Quantum Cosmology · Physics 2015-04-03 Joan Sola , Adria Gomez-Valent

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

Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 David I. Kaiser
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