English
Related papers

Related papers: Second-order Lagrangian perturbation theory initia…

200 papers

Initial conditions for (Newtonian) cosmological N-body simulations are usually set by re-scaling the present-day power spectrum obtained from linear (relativistic) Boltzmann codes to the desired initial redshift of the simulation. This…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Christian Fidler , Thomas Tram , Cornelius Rampf , Robert Crittenden , Kazuya Koyama , David Wands

We test third-order standard perturbation theory (SPT) as an approximation to non-linear cosmological structure formation. A novel approach is used to numerically calculate the three-dimensional dark matter density field using SPT from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Nina Roth , Cristiano Porciani

Associating the formation sites of haloes with the maxima of the smoothed linear density field, we present non-perturbative predictions for the Lagrangian and evolved halo correlation functions that are valid at all separations. In…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-05 Tobias Baldauf , Sandrine Codis , Vincent Desjacques , Christophe Pichon

We study analytically the collapse of an initially smooth, cold, self-gravitating collisionless system in one dimension. The system is described as a central "S" shape in phase-space surrounded by a nearly stationary halo acting locally…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Stephane Colombi

On the smallest scales, three-dimensional large-scale structure surveys contain a wealth of cosmological information which cannot be trivially extracted due to the non-linear dynamical evolution of the density field. Lagrangian perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-05 Florent Leclercq , Jens Jasche , Héctor Gil-Marín , Benjamin Wandelt

This is part two in a series of papers in which we investigate an approach based on Lagrangian perturbation theory (LPT) to study the non-linear evolution of the large-scale structure distribution in the universe. Firstly, we compute the…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-15 Cornelius Rampf , Yvonne Y. Y. Wong

Dark matter haloes play a fundamental role in cosmological structure formation. The most common approach to model their assembly mechanisms is through N-body simulations. In this work we present an innovative pathway to predict dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Mauro Bernardini , Lucio Mayer , Darren Reed , Robert Feldmann

We use gauge-invariant cosmological perturbation theory to calculate the displacement field that sets the initial conditions for $N$-body simulations. Using first and second-order fully relativistic perturbation theory in the…

General Relativity and Quantum Cosmology · Physics 2016-03-02 Adam J. Christopherson , Juan Carlos Hidalgo , Cornelius Rampf , Karim A. Malik

We study the statistical properties (such as shape and spin) of high-z halos likely hosting the first (PopIII) stars with cosmological simulations including detailed gas physics. In the redshift range considered ($11 < z < 16$) the average…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-03 Rafael S. de Souza , Benedetta Ciardi , Umberto Maio , Andrea Ferrara

We investigate the effect of long-range scalar interactions in dark matter (DM) models of cosmic structure formation with a particular focus on the formation times of haloes. Utilising $N$-body simulations with $512^3$ DM particles we show…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-20 Wojciech A. Hellwing , Steffen R. Knollmann , Alexander Knebe

Numerical simulations show that redshift space distortions (RSD) introduce strong scale dependence in the power spectra of halos, with ten percent deviations relative to linear theory predictions even on relatively large scales (k<0.1h/Mpc)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Zvonimir Vlah , Uroš Seljak , Teppei Okumura , Vincent Desjacques

This paper uses numerical simulations to test the formation time distribution of dark matter haloes predicted by the analytic excursion set approaches. The formation time distribution is closely linked to the conditional mass function and…

Astrophysics · Physics 2009-11-10 W. P. Lin , Y. P. Jing , Lihwai Lin

We present a detailed description and validation of our massively-parallel update to the mass-Peak Patch method, a fully predictive initial-space algorithm to quickly generate dark matter halo catalogues in very large cosmological volumes.…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 George Stein , Marcelo A. Alvarez , J. Richard Bond

We consider the growth of primordial dark matter halos seeded by three crossed initial sine waves of various amplitudes. Using a Lagrangian treatment of cosmological gravitational dynamics, we examine the convergence properties of a…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-18 Shohei Saga , Atsushi Taruya , Stéphane Colombi

We present a simple method of generating approximate synthetic halo catalogues: HALOGEN. This method uses a combination of $2^{nd}$-order Lagrangian Perturbation Theory (2LPT) in order to generate the large-scale matter distribution,…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-08 Santiago Avila , Steven G. Murray , Alexander Knebe , Chris Power , Aaron S. G. Robotham , Juan Garcia-Bellido

This paper deals with the time evolution in the matter era of perturbations in Friedman-Lemaitre models with arbitrary density parameter $\Omega$, with either a zero cosmological constant, $\Lambda = 0$, or with a non-zero cosmological…

Astrophysics · Physics 2011-05-23 F. R. Bouchet , S. Colombi , E. Hivon , R. Juszkiewicz

Using a series of high-resolution N-body simulations of the concordance cosmology we investigate how the formation histories, shapes and angular momenta of dark-matter haloes depend on environment. We first present a classification scheme…

Astrophysics · Physics 2008-11-26 Oliver Hahn , Cristiano Porciani , C. Marcella Carollo , Avishai Dekel

Understanding the formation of the first objects in the universe critically depends on knowing whether the properties of small dark matter structures at high-redshift (z > 15) are different from their more massive lower-redshift…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-19 Mei Sasaki , Paul C. Clark , Volker Springel , Ralf S. Klessen , Simon C. O. Glover

Small fraction of isocurvature perturbations may exist and correlate with adiabatic perturbations in the primordial perturbations. Naively switching off isocurvature perturbations may lead to biased results. We study the effect of dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jie Liu

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