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Related papers: Non-linear Fields in Generalized Cosmologies

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We present a new analytic approach to describe large scale structure formation in the mildly non-linear regime. The central object of the method is the time-dependent probability distribution function generating correlators of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-09 Diego Blas , Mathias Garny , Mikhail M. Ivanov , Sergey Sibiryakov

We investigate the third-order density perturbation and the one-loop correction to the linear power spectrum in the dark-energy cosmological model. Our main interest is to understand the dark-energy effect on baryon acoustic oscillations in…

Astrophysics · Physics 2008-12-18 Ryuichi Takahashi

We propose and construct a two-parameter perturbative expansion around a Friedmann-Lema\^{i}tre-Robertson-Walker geometry that can be used to model high-order gravitational effects in the presence of non-linear structure. This framework…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-15 Sophia R. Goldberg , Timothy Clifton , Karim A. Malik

In this paper we present four simple expressions for the relativistic first and second order fractional density perturbations for $\Lambda$CDM cosmologies in different gauges: the Poisson, uniform curvature, total matter and synchronous…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Claes Uggla , John Wainwright

Local nonlinear approximations to the growth of cosmic perturbations are developed, resulting in relations, at a given epoch, between the peculiar velocity and gravity fields and their gradients. Only the equation of motion is approximated,…

Astrophysics · Physics 2009-10-22 Paul J. Mancinelli , Amos Yahil

This paper presents an analytical formula that closely approximates the fully nonlinear power spectrum of matter fluctuations for redshift $z\approx 5$ to 0 over a wide range of cosmologically interesting flat models with varying matter…

Astrophysics · Physics 2009-10-30 Chung-Pei Ma

Effective field theory provides a perturbative framework to study the evolution of cosmological large-scale structure. We investigate the underpinnings of this approach, and suggest new ways to compute correlation functions of cosmological…

High Energy Physics - Theory · Physics 2014-07-16 Sean M. Carroll , Stefan Leichenauer , Jason Pollack

Cosmological linear perturbation theory predicts that the peculiar velocity $V(x)$ and the matter overdensity $\delta(x)$ at a same point $x$ are statistically independent quantities, as log as the initial density fluctuations are random…

Astrophysics · Physics 2009-10-31 Naoki Seto

We investigate the impact of a common approximation on weak lensing power spectra: the use of single-epoch matter power spectra in integrals over redshift. We disentangle this from the closely connected Limber's approximation. We derive the…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-11 Lucia F. de la Bella , Nicolas Tessore , Sarah Bridle

Nonlinear field theories can be used to study both standard physics questions, or to study questions such as the emergence of order and complexity. These theories are generally derived from the symmetries of a given problem and the…

Adaptation and Self-Organizing Systems · Physics 2007-09-14 Joel Thorarinson , Marcelo Gleiser

We allow for nonlinear effects in the likelihood analysis of galaxy peculiar velocities, and obtain ~35%-lower values for the cosmological density parameter Om and the amplitude of mass-density fluctuations. The power spectrum in the linear…

Astrophysics · Physics 2009-11-06 L. Silberman , A. Dekel , A. Eldar , I. Zehavi

We estimate the power spectrum of mass density fluctuations from peculiar velocities of galaxies by applying an improved maximum-likelihood technique to the new all-sky SFI catalog. Parametric models are used for the power spectrum and the…

We study the third order solutions of the cosmological density perturbations in the Horndeski's most general scalar-tensor theory under the condition that the Vainshtein mechanism is at work. In this work, we thoroughly investigate the…

General Relativity and Quantum Cosmology · Physics 2015-11-25 Yuichiro Takushima , Ayumu Terukina , Kazuhiro Yamamoto

Generalised axion-like scalar fields provide a well-motivated framework for describing the late-time acceleration of the Universe. As the field evolves, it rolls down its potential and, depending on its mass and initial conditions, it may…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-30 Mariam Bouhmadi-López , Carlos G. Boiza

A quintessence scalar field or cosmon interacting with neutrinos can have important effects on cosmological structure formation. Within growing neutrino models the coupling becomes effective only in recent times, when neutrinos become…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-29 Nico Wintergerst , Valeria Pettorino , David F. Mota , Christof Wetterich

The anisotropy of clustering in redshift space provides a direct measure of the growth rate of large scale structure in the Universe. Future galaxy redshift surveys will make high precision measurements of these distortions, and will…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 Elise Jennings , Carlton M. Baugh , Silvia Pascoli

Several recent studies have shown how to properly calculate the observed clustering of galaxies in a relativistic context, and uncovered corrections to the Newtonian calculation that become significant on scales near the horizon. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Donghui Jeong , Fabian Schmidt , Christopher M. Hirata

We use the recently developed Kinetic Field Theory (KFT) for cosmic structure formation to show how non-linear power spectra for cosmic density fluctuations can be calculated in a mean-field approximation to the particle interactions. Our…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-23 Matthias Bartelmann , Johannes Dombrowski , Sara Konrad , Elena Kozlikin , Robert Lilow , Carsten Littek , Christophe Pixius , Felix Fabis

The power spectrum of mass density fluctuations is estimated from the Mark III and the SFI catalogs of peculiar velocities by applying a maximum likelihood analysis, using parametric models for the power spectrum and for the errors.…

Astrophysics · Physics 2007-05-23 Idit Zehavi

We investigate the non-gaussian properties of cosmic-string-seeded linear density perturbations with cold and hot dark matter backgrounds, using high-resolution numerical simulations. We compute the one-point probability density function of…

Astrophysics · Physics 2009-10-30 P. P. Avelino , E. P. S. Shellard , J. H. P. Wu , B. Allen
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