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Related papers: Cosmological Distribution Functions

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In the context of f(R) theories of gravity, we study the cosmological evolution of scalar perturbations by using a completely general procedure. We find that the exact fourth-order differential equation for the matter density perturbations…

Astrophysics · Physics 2015-05-13 A. de la Cruz-Dombriz , A. Dobado , A. L. Maroto

The Vlasov equation for the collisionless evolution of the single-particle probability distribution function (PDF) is a well-known Lie-Poisson Hamiltonian system. Remarkably, the operation of taking the moments of the Vlasov PDF preserves…

Exactly Solvable and Integrable Systems · Physics 2008-04-25 John Gibbons , Darryl D Holm , Cesare Tronci

We study the one-point probability distribution function (PDF) for matter density averaged over spherical cells. The leading part to the PDF is defined by spherical collapse dynamics, whereas the next-to-leading part comes from the…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-08 Anton Chudaykin , Mikhail M. Ivanov , Sergey Sibiryakov

Numerical evidence of non-diffusive transport in three-dimensional, resistive pressure-gradient-driven plasma turbulence is presented. It is shown that the probability density function (pdf) of test particles' radial displacements is…

Plasma Physics · Physics 2009-11-10 D. del-Castillo-Negrete , B. A. Carreras , V. E. Lynch

The 1-point matter density probability distribution function (PDF) captures some of the non-Gaussian information lost in standard 2-point statistics. The matter PDF can be well predicted at mildly non-linear scales using large deviations…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-16 Beth McCarthy Gould , Lina Castiblanco , Cora Uhlemann , Oliver Friedrich

Continuum dislocation dynamics (CDD) represents the evolution of systems of curved and connected dislocation lines in terms of density-like field variables which include the volume density of loops (or 'curvature density') as an additional…

Materials Science · Physics 2023-01-04 Xi Luo , Michael Zaiser

The ``Newtonian'' theory of spatially unbounded, self--gravitating, pressureless continua in Lagrangian form is reconsidered. Following a review of the pertinent kinematics, we present alternative formulations of the Lagrangian evolution…

Astrophysics · Physics 2015-06-24 Juergen Ehlers , Thomas Buchert

We study the inhomogeneous cosmological evolution of the Newtonian gravitational 'constant' G in the framework of scalar-tensor theories. We investigate the differences that arise between the evolution of G in the background universes and…

General Relativity and Quantum Cosmology · Physics 2009-09-29 T. Clifton , D. F. Mota , J. D. Barrow

The normal distribution is used as a unified probability distribution, however, our researcher found that it is not good agreed with the real-life dynamical system's data. We collected and analyzed representative naturally occurring data…

Dynamical Systems · Mathematics 2020-11-06 Wei Ping Cheng , Zhi Hong Zhang , Pu Wang

The problem of solving perturbatively the equations describing the evolution of self-gravitating collisionless matter in an expanding universe considerably simplifies when directly formulated in terms of the gravitational and velocity…

Astrophysics · Physics 2015-06-24 Paolo Catelan , Francesco Lucchin , Sabino Matarrese , Lauro Moscardini

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

Under ideal conditions, the probability density function (PDF) of a random variable, such as a sensor measurement, would be well known and amenable to computation and communication tasks. However, this is often not the case, so the user…

Statistics Theory · Mathematics 2022-07-29 Shane Lubold , Clark N. Taylor

In a mean-field approximation within Kinetic Field Theory, it is possible to derive an accurate analytic expression for the power spectrum of present-day non-linear cosmic density fluctuations. It depends on the theory of gravity and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 Alexander Oestreicher , Harshda Saxena , Niklas Reinhardt , Elena Kozlikin , Johannes Dombrowski , Matthias Bartelmann

Non-linear cosmic structures contain valuable information on the expansion history of the background space-time, the nature of dark matter, and the gravitational interaction. The recently developed kinetic field theory of cosmic structure…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-18 Alexander Oestreicher , Lodovico Capuano , Sabino Matarrese , Lavinia Heisenberg , Matthias Bartelmann

(Abridged) We discuss the probability distribution function (PDF) of column density resulting from density fields with lognormal PDFs, applicable to isothermal gas (e.g., probably molecular clouds). We suggest that a ``decorrelation…

Astrophysics · Physics 2009-11-06 Enrique Vazquez-Semadeni , Nieves Garcia

For general number of spatial dimensions we investigate the cosmological dynamics driven by a cosmological constant and by a source with barotropic equation of state. It is assumed that for both those sources the energy density can be…

General Relativity and Quantum Cosmology · Physics 2022-11-09 A. A. Saharian , R. M. Avagyan , E. R. Bezerra de Mello , V. Kh. Kotanjyan , T. A. Petrosyan , H. G. Babujyan

The cosmic web is a complex spatial pattern of walls, filaments, cluster nodes and underdense void regions. It emerged through gravitational amplification from the Gaussian primordial density field. Here we infer analytical expressions for…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-17 Job Feldbrugge , Johan Hidding , Rien van de Weygaert

The one-point probability distribution function (PDF) is a powerful summary statistic for non-Gaussian cosmological fields, such as the weak lensing (WL) convergence reconstructed from galaxy shapes or cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Leander Thiele , J. Colin Hill , Kendrick M. Smith

The large-scale structure in cosmology is highly non-Gaussian at late times and small length scales, making it difficult to describe analytically. Parameter inference, data reconstruction, and data generation tasks in cosmology are greatly…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-13 Adam Rouhiainen

Diffusion tensor coefficients play a central role in describing cosmic-ray transport in various astrophysical environments permeated with magnetic fields, which are usually modeled as a fluctuating field on top of a mean field. In this…

High Energy Astrophysical Phenomena · Physics 2024-07-09 O. Deligny
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