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Related papers: Cosmology in One Dimension: Vlasov Dynamics

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We present a new high-resolution N-body algorithm for cosmological simulations. The algorithm employs a traditional particle-mesh technique on a cubic grid and successive multilevel relaxations on the finer meshes, introduced recursively in…

Astrophysics · Physics 2009-10-30 Andrey V. Kravtsov , Anatoly A. Klypin , Alexei M. Khokhlov

The Vlasov-Poisson system describes interacting systems of collisionless particles. For solutions with small initial data in three dimensions it is known that the spatial density of particles decays like $t^{-3}$ at late times. In this…

Analysis of PDEs · Mathematics 2007-05-23 Hyung Ju Hwang , Alan D. Rendall , Juan J. L. Velazquez

We consider the dynamics of N bosons in one dimension. We assume that the pair interaction is attractive and given by N^{\beta -1}V(N^{\beta}\cdot) where \int V\leqslant 0. We develop new techniques in treating the N-body Hamiltonian so…

Analysis of PDEs · Mathematics 2016-04-21 Xuwen Chen , Justin Holmer

We obtain a new exact equilibrium solution to the N-body problem in a one-dimensional relativistic self-gravitating system. It corresponds to an expanding/contracting spacetime of a circle with N bodies at equal proper separations from one…

General Relativity and Quantum Cosmology · Physics 2017-08-23 R. Kerner , R. B. Mann

We perform N-body simulations for $f(T)$ gravity using the ME-Gadget code, in order to investigate for the first time the structure formation process in detail. Focusing on the power-law model, and considering the model-parameter to be…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Yiqi Huang , Jiajun Zhang , Xin Ren , Emmanuel N. Saridakis , Yi-Fu Cai

Initial conditions for cosmological N-body simulations are usually calculated by rescaling the present day linear power spectrum obtained from an Einstein-Boltzmann solver to the initial time employing the scale-independent matter growth…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-12 Christian Fidler , Alexander Kleinjohann

The results of our study of the motion of a three particle, self-gravitating system in general relativistic lineal gravity is presented for an arbitrary ratio of the particle masses. We derive a canonical expression for the Hamiltonian of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. J. Malecki , R. B. Mann

The interstellar medium is observed in a hierarchical fractal structure over several orders of magnitude in scale. Aiming to understand the origin of this structure, we carry out numerical simulations of molecular cloud fragmentation,…

Astrophysics · Physics 2007-05-23 B. Semelin , F. Combes

High resolution dark matter only simulations provide a realistic and fully general means to study the theoretical predictions of cosmological structure formation models for gravitational lensing. Due to the finite number of particles, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Stefan Rau , Simona Vegetti , Simon D. M. White

In virtual worlds, objects fall straight down. By replacing a few lines of code to include Newton's gravity, virtual world software can become an N-body simulation code with visualization included where objects move under their mutual…

Instrumentation and Methods for Astrophysics · Physics 2009-09-30 Will M. Farr , Piet Hut , Jeff Ames , Adam Johnson

We propose a new numerical procedure to simulate a single dark halo of any size and mass in a hierarchical framework coupling the extended Press-Schechter formalism (EPSF) to N-body simulations. The procedure consists of assigning…

Astrophysics · Physics 2009-11-07 Elena D'Onghia , Claudio Firmani , Guido Chincarini

In spite of the growing observational evidence for dark matter and dark energy in the universe, their physical nature is largely unknown. In fact, several authors have proposed modifications of Newton's law of gravity at cosmological scales…

Astrophysics · Physics 2009-11-10 Akihito Shirata , Tetsuya Shiromizu , Naoki Yoshida , Yasushi Suto

Cosmological N-body simulations are now being performed using Newtonian gravity on scales larger than the Hubble radius. It is well known that a uniformly expanding, homogeneous ball of dust in Newtonian gravity satisfies the same equations…

General Relativity and Quantum Cosmology · Physics 2012-04-02 Stephen R. Green , Robert M. Wald

We intend to make sets of cosmological simulations available, with a large number of different output times that may be placed side-by-side to produce a complete history of the universe stretching back to high redshift. Currently there is…

Astrophysics · Physics 2007-05-23 P. A. Thomas , H. M. P. Couchman , F. R. Pearce

We present a numerical code for multi-component simulation of the galactic evolution. Our code includes the following parts: $N$-body is used to evolve dark matter, stellar dynamics and dust grains, gas dynamics is based on TVD-MUSCL scheme…

Computational Physics · Physics 2015-02-11 S. A. Khoperskov , E. O. Vasiliev , A. V. Khoperskov , V. N. Lubimov

The current paradigm for understanding galaxy formation in the universe depends on the existence of self-gravitating collisionless dark matter. Modeling such dark matter systems has been a major focus of astrophysicists, with much of that…

Astrophysics of Galaxies · Physics 2015-06-17 Eric I. Barnes , Robert J. Ragan

We investigate the cosmology of a recently proposed deformation of Einstein gravity, emerging from quantum gravity heuristics. The theory is constructed to have de Sitter space as a vacuum solution, and thus to be relevant to the…

We discuss the relation between the output of Newtonian N-body simulations on scales that approach or exceed the particle horizon to the description of General Relativity. At leading order, the Zeldovich approximation is correct on large…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-27 Cornelius Rampf , Gerasimos Rigopoulos , Wessel Valkenburg

The advent of the new generation of wide field galaxy surveys makes large N-body cosmological simulations a necessary evil. While the cosmological simulation codes have evolved a lot since the first calculations in the 80s, the…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Claudio Llinares

The distribution of galaxies, halo abundance, and peculiar velocities are influenced by non-linear gravitational interactions, making the study of non-linear evolution crucial for accurate cosmological predictions. We explore these aspects…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-24 Swati Gavas
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