English
Related papers

Related papers: Relativistic initial conditions for N-body simulat…

200 papers

The $\nu$HDM is the only cosmological model based on Milgromian Dynamics (MOND) with available structure formation simulations. While MOND accounts for galaxies, with a priori predictions for spirals and ellipticals, a light sterile…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-25 Nick Samaras , Sebastian Grandis , Pavel Kroupa

This paper presents a general-relativistic N-body technique for evolving the phase space distribution of massive neutrinos in linear perturbation theory. The method provides a much more accurate sampling of the neutrino phase space for the…

Astrophysics · Physics 2009-10-22 Chung-Pei Ma , Edmund Bertschinger

Gravitational softening length is one of the key parameters to properly set up a cosmological $N$-body simulation. In this paper, we perform a large suit of high-resolution $N$-body simulations to revise the optimal softening scheme…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-07 Tianchi Zhang , Shihong Liao , Ming Li , Liang Gao

Several extensions of the standard cosmological model include scalar fields as new degrees of freedom in the underlying gravitational theory. A particular class of these scalar field theories include screening mechanisms intended to hide…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David F. Mota , Hans A. Winther

We present $\Lambda$CDM $N$-body cosmological simulations in the framework of a static general scalar-tensor theory of gravity. Due to the influence of the non-minimally coupled scalar field, the gravitational potential is modified by a…

In the standard concordance cosmology the spatial curvature is assumed to be constant and zero (or at least very small). In particular, in numerical computations of the structure of the universe using N-body simulations, exact periodic…

General Relativity and Quantum Cosmology · Physics 2023-12-07 Alan Coley , Woei Chet Lim

Testing gravity and the concordance model of cosmology, $\Lambda$CDM, at large scales is a key goal of this decade's largest galaxy surveys. Here we present a comparative study of dark matter power spectrum predictions from different…

We review the field of collisionless numerical simulations for the large-scale structure of the Universe. We start by providing the main set of equations solved by these simulations and their connection with General Relativity. We then…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-14 Raul E. Angulo , Oliver Hahn

In the present work, we study for the first time a scale--dependent gravitational theory in a cosmological context in a matter--dominated era. In particular, starting from the Einstein Hilbert action with cosmological constant assuming…

General Relativity and Quantum Cosmology · Physics 2018-07-13 A. Hernández-Arboleda , Á. Rincón , B. Koch , E. Contreras , P. Bargueño

We describe some results obtained with N-MODY, a code for N-body simulations of collisionless stellar systems in modified Newtonian dynamics (MOND). We found that a few fundamental dynamical processes are profoundly different in MOND and in…

Astrophysics · Physics 2015-05-13 Carlo Nipoti , Pasquale Londrillo , Luca Ciotti

We use N-body simulation to study the structure formation in the Cubic Galileon Gravity model where along with the usual kinetic and potential term we also have a higher derivative self-interaction term. We find that the large scale…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 Jiajun Zhang , Bikash R. Dinda , Md. Wali Hossain , Anjan A. Sen , Wentao Luo

State-of-the-art cosmological simulations on classical computers are limited by time, energy, and memory usage. Quantum computers can perform some calculations exponentially faster than classical computers, using exponentially less energy…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 Philip Mocz , Aaron Szasz

We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Christian Wagner , Licia Verde , Lotfi Boubekeur

We study the structure and substructure of halos obtained in N-body simulations for a Lambda Cold Dark Matter (LCDM) cosmology with non-Gaussian initial conditions (NGICs). The initial statistics are lognormal in the gravitational potential…

Astrophysics · Physics 2008-11-26 V. Avila-Reese , P. Colin , G. Piccinelli , C. Firmani

Non-linear evolution of cosmological energy density fluctuations triggers deviations from Gaussianity in the temperature distribution of the cosmic microwave background. A method to estimate these deviations is proposed. N-body simulations…

Astrophysics · Physics 2009-11-07 A. M. Aliaga , V. Quilis , J. V. Arnau , D. Saez

We present GRAMSES, a new pipeline for nonlinear cosmological $N$-body simulations in General Relativity (GR). This code adopts the Arnowitt-Deser-Misner (ADM) formalism of GR, with constant mean curvature and minimum distortion gauge…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-24 Cristian Barrera-Hinojosa , Baojiu Li

In the context of scalar tensor theories for gravity, there is a universally adopted hypothesis when running N-body simulations that time derivatives in the equation of motion for the scalar field are negligible. In this work we propose to…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David F. Mota

Accurate cosmological simulations that include the effect of non-linear matter clustering as well as of massive neutrinos are essential for measuring the neutrino mass scale from upcoming galaxy surveys. Typically, Newtonian simulations are…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-24 Christian Partmann , Christian Fidler , Cornelius Rampf , Oliver Hahn

Recent calculations in loop quantum cosmology suggest that a transition from a Lorentzian to an Euclidean space-time might take place in the very early Universe. The transition point leads to a state of silence, characterized by a vanishing…

General Relativity and Quantum Cosmology · Physics 2017-12-07 Jakub Mielczarek , Linda Linsefors , Aurelien Barrau

In this paper, we describe the first steps towards fully non-perturbative cosmology. We explain why the conventional methods used by cosmologists based on the ADM formulation are generally inadequate for this purpose and why it is…

General Relativity and Quantum Cosmology · Physics 2019-01-08 Anna Ijjas , Frans Pretorius , Paul J. Steinhardt