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Related papers: Cosmology in One Dimension: Vlasov Dynamics

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We present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael D. Schneider , Shaun Cole , Carlos S. Frenk , Istvan Szapudi

The Vlasov-Poisson systems of equations (VP) describes the evolution of a distribution of collisionless particles under the effect of a collective-field potential. VP is at the basis of the study of the gravitational instability of…

We present the new relativistic cosmological particle-mesh code $\texttt{fRevolution}$, based on $\texttt{gevolution}$, aimed at simulating non-linear structure formation in $f(R)$ gravity. We introduce the general framework and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-31 Lorenzo Reverberi , David Daverio

In setting up initial conditions for ensembles of cosmological N-body simulations there are, fundamentally, two choices: either maximizing the correspondence of the initial density field to the assumed fourier-space clustering or, instead,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Chris Orban

We present the UNIT $N$-body cosmological simulations project, designed to provide precise predictions for nonlinear statistics of the galaxy distribution. We focus on characterizing statistics relevant to emission line and luminous red…

Large redshift surveys of galaxies and clusters are providing the first opportunities to search for distortions in the observed pattern of large-scale structure due to such effects as gravitational redshift. We focus on non-linear scales…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-25 Hongyu Zhu , Shadab Alam , Rupert A. C. Croft , Shirley Ho , Elena Giusarma

We present a new method for generating initial conditions for numerical cosmological simulations in which massive neutrinos are treated as an extra set of N-body (collisionless) particles. It allows us to accurately follow the density field…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Arka Banerjee , Devon Powell , Tom Abel , Francisco Villaescusa-Navarro

Several N-body problems in ordinary (3-dimensional) space are introduced which are characterized by Newtonian equations of motion (``acceleration equal force;'' in most cases, the forces are velocity-dependent) and are amenable to exact…

Mathematical Physics · Physics 2015-06-26 Massimo Bruschi , Francesco Calogero

We provide a detailed analysis of Friedmann-Robertson-Walker universes in a wide range of scalar-tensor theories of gravity. We apply solution-generating methods to three parametrised classes of scalar-tensor theory which lead naturally to…

General Relativity and Quantum Cosmology · Physics 2009-10-28 John D. Barrow , Paul Parsons

Modelling gravity is a fundamental problem that must be tackled in N-body simulations of stellar systems, and satisfactory solutions require a deep understanding of the dynamical effects of softening. In a previous paper (Romeo 1997), we…

Astrophysics · Physics 2007-05-23 Alessandro B. Romeo

We consider a system representing self-gravitating balls of dust in an expanding Universe. It is demonstrated that one can prescribe data for such a system at infinity and evolve it backward in time without the development of shocks or…

General Relativity and Quantum Cosmology · Physics 2022-06-29 Shabnam Beheshti , Mikael Normann , Juan Valiente Kroon

I begin with a brief history of N-body simulation and visualization and then go on to describe various methods for creating images and animations of modern simulations in cosmology and galactic dynamics. These techniques are incorporated…

Astrophysics · Physics 2008-12-18 John Dubinski

By using, the Vlasov-Poisson equation defined in either a Riemannian or a semi-Riemannian space $\mathbb{R}^k_g$, and a Dirac distribution function, we re-obtain the well known and classical equations of motion of a mechanical system with a…

Dynamical Systems · Mathematics 2014-12-30 Pedro Pablo Ortega Palencia , J. Guadalupe Reyes Victoria

Modified gravity theories constitute viable alternatives to the standard cosmological model for explaining the observed late-time accelerated expansion of the Universe. The Effective Field Theory of Dark Energy (EFTofDE) is an efficient…

The N-body gauge allows the introduction of relativistic effects in Newtonian cosmological simulations. Here we extend this framework to general Horndeski gravity theories, and investigate the relativistic effects that the scalar field…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-22 Guilherme Brando , Kazuya Koyama , David Wands , Miguel Zumalacárregui , Ignacy Sawicki , Emilio Bellini

The Vlasov-Poisson equation is a classical example of an effective equation which shall describe the coarse-grained time evolution of a system consisting of a large number of particles which interact by Coulomb or Newton's gravitational…

Mathematical Physics · Physics 2021-05-17 Phillip Grass

Relativistic numerical cosmology is most often based either on the exact solutions of the Einstein equations, or perturbation theory, or weak-field limit, or the BSSN formalism. The Silent Universe provides an alternative approach to…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-08 Krzysztof Bolejko

The large-scale statistics of observables such as the galaxy density are chiefly determined by their dependence on the local coarse-grained matter density. This dependence can be measured directly and efficiently in N-body simulations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Christian Wagner , Fabian Schmidt , Chi-Ting Chiang , Eiichiro Komatsu

We develop a new approach to building cosmological models, in which small pieces of perturbed Minkowski space are joined together at reflection-symmetric boundaries in order to form a global, dynamical space-time. Each piece of this…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Viraj A. A. Sanghai , Timothy Clifton

Cosmological simulations describing the evolution of density perturbations of a self-gravitating collisionless Dark Matter (DM) fluid in an expanding background, provide a powerful tool to follow the formation of cosmic structures over wide…

Quantum Physics · Physics 2024-01-29 Luca Cappelli , Francesco Tacchino , Giuseppe Murante , Stefano Borgani , Ivano Tavernelli
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