English
Related papers

Related papers: Second-order Lagrangian perturbation theory initia…

200 papers

The standard numerical tools for studying non-linear collapse of matter are Newtonian $N$-body simulations. Previous work has shown that these simulations are in accordance with General Relativity (GR) up to first order in perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-07 Christian Fidler , Thomas Tram , Cornelius Rampf , Robert Crittenden , Kazuya Koyama , David Wands

Both simulation and observational data have shown that the spin and shape of dark matter halos are correlated with their nearby large-scale environment. As structure formation on different scales is strongly coupled, it is trick to…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-27 Hou-Zun Chen , Xi Kang , Peng Wang , Noam I. Libeskind , Yu Luo

The Lagrangian perturbation theory on Friedmann-Lemaitre cosmologies is compared with numerical simulations (tree-, adaptive P$^3$M- and PM codes). In previous work we have probed the large-scale performance of the Lagrangian perturbation…

Astrophysics · Physics 2011-05-23 G. Karakatsanis , T. Buchert , A. L. Melott

This paper aims at quantifying discreetness effects, born of finite particle number, on the dynamics of dark matter haloes forming in the context of cosmological simulations. By generalising the standard calculation of two body relaxation…

Astrophysics · Physics 2009-11-11 Amr El-Zant

We present results from three-dimensional hydrodynamic simulations of the high redshift collapse of pregalactic clouds including feedback effects from a soft H2 photodissociating UV radiation field. The simulations use an Eulerian adaptive…

Astrophysics · Physics 2009-10-31 Marie E. Machacek , Greg L. Bryan , Tom Abel

We perform for the first time high-resolution zoom-in re-simulations of individual halos in the context of the Multi-coupled Dark Energy (McDE) scenario, which is characterised by the existence of two distinct dark matter particle species…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-05 E. Garaldi , M. Baldi , L. Moscardini

The analysis of cosmological galaxy surveys requires realistic simulations for their interpretation. Forward modelling is a powerful method to simulate galaxy clustering without the need for an underlying complex model. This approach…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-07 Pascale Berner , Alexandre Refregier , Raphael Sgier , Tomasz Kacprzak , Luca Tortorelli , Pierluigi Monaco

We present "sheet+release" simulations that reliably follow the evolution of dark matter structure at and below the dark matter free-streaming scale, where instabilities in traditional N-body simulations create a large population of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 Jens Stücker , Raul E. Angulo , Oliver Hahn , Simon D. M. White

We describe cosmological simulation techniques and their application to studies of cosmic structure formation, with particular attention to recent hydrodynamic simulations of structure in the high redshift universe. Collisionless N-body…

Astrophysics · Physics 2008-02-03 David H. Weinberg , Neal Katz , Lars Hernquist

The initial conditions for Newtonian $N$-body simulations are usually generated by applying the Zel'dovich approximation to the initial displacements of the particles using an initial power spectrum of density fluctuations generated by an…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-23 Christian Fidler , Cornelius Rampf , Thomas Tram , Robert Crittenden , Kazuya Koyama , David Wands

We update Halo Zeldovich Perturbation Theory (HZPT), an analytic model for the two-point statistics of dark matter, to describe halo and galaxy clustering, and galaxy-matter cross-correlation on nonlinear scales. The model correcting…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 James M. Sullivan , Uros Seljak , Sukhdeep Singh

We compare relativistic approximation methods, which describe gravitational instability in the expanding universe, in a spherically symmetric model. Linear perturbation theory, second-order perturbation theory, relativistic Zel'dovich…

Astrophysics · Physics 2014-10-13 Masaaki Morita , Kouji Nakamura , Masumi Kasai

We study the impact of numerical parameters on the properties of cold dark matter haloes formed in collisionless cosmological simulations. We quantify convergence in the median spherically-averaged circular velocity profiles for haloes of…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Aaron D. Ludlow , Joop Schaye , Richard Bower

We present an iterative method to reconstruct the linear-theory initial conditions from the late-time cosmological matter density field, with the intent of improving the recovery of the cosmic distance scale from the baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-05 Ryuichiro Hada , Daniel J. Eisenstein

We study the phase-space structure of a dark-matter halo formed in a high resolution simulation of a Lambda CDM cosmology. Our goal is to quantify how much substructure is left over from the inhomogeneous growth of the halo, and how it may…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

We present a pipeline for characterizing and constraining initial conditions in cosmology via persistent homology. The cosmological observable of interest is the cosmic web of large scale structure, and the initial conditions in question…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-08 Alex Cole , Matteo Biagetti , Gary Shiu

We present and test a method for modifying the catalogue of dark matter haloes produced from a given cosmological simulation, so that it resembles the result of a simulation with an entirely different set of parameters. This extends the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-02 Alexander Mead , John Peacock

We use a novel technique to simulate the growth of the most massive progenitor of a protocluster region from redshift z~80, when its mass was about 10 Msun until the present day. Our nested sequence of N-body resimulations allows us to…

Astrophysics · Physics 2009-09-25 Liang Gao , Simon D. M. White , Adrian Jenkins , Carlos Frenk , Volker Springel

We address the generation of initial conditions (ICs) for GRAMSES, a code for nonlinear general relativistic (GR) $N$-body cosmological simulations recently introduced in Ref. [1]. GRAMSES adopts a constant mean curvature slicing with a…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-06 Cristian Barrera-Hinojosa , Baojiu Li

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