Evidence of turbulence-like universality in the formation of galaxy-sized dark matter haloes

Abstract

Context. Although the theoretical understanding of nonlinear gravitational clustering has greatly advanced in the last decades, in particular by improvements in numerical N-body simulations, the physics behind this process is not fully elucidated. Aims. The main goal of this work is the study of the possibility of a turbulent-like physical process in the formation of structures, galaxies and clusters of galaxies, by the action of gravity alone. Methods. We use simulation data from the Virgo Consortium, in ten redshift snapshots (from 0 to 10). From this we identify galaxysized and cluster-sized dark matter haloes, by using a FoF algorithm and applying a boundedness criterion, and study the gravitational potential energy spectra. Results. We find that the galaxy-sized halo energy spectrum follows closely a Kolmogorov power law, similar to the behaviour of dynamically turbulent processes in fluids.Conclusions. This means that the gravitational clustering of dark matter may admit a turbulent-like representation.

The Brazilian Virtual Observatory - A New Paradigm for Astronomy

“…Therefore, a post-processing procedure is applied to examine objects close to a boundary but with a valid friend in an adjacent sub-domain. Our parallel version has fully reproduced previous results [5] for computing the potential gravitational energy spectrum for galaxies and clusters of galaxies at many redshifts. A VO service will be made available allowing the user to run the FoF algorithm over the most important cosmological simulations available to date as well as those inputed by the user.…”

Modelagem Matemática em Turbulência Atmosférica

“…Analisando dados do Consórcio Virgo, com número de partículas N = 2563 (cada partícula tem massa de 6, 86 × 10 10 M , a massa bariônica da Via Lactea), dentro de um cubo de aresta L = 239.5 h −1 Mpc, com taxa de expansão h = 0, 7 (h = H 0 /100 Km s −1 ); as LSS são consideradas após uma análise de grupamento, empregando um processo de percolação [19]. A simulação de N -corposé realizada com o modelo Λ-CDM (Λ expressa o valor da constante cosmológica e CDMé o acrônimo para Cold Dark Matter ).…”

“…Alternativamente, pode-se construir espectros de energia potencial gravitacional sob a ação da matéria escura. O cálculoé realizado considerando-se cada halo em cascas concêntricas, onde a energia gravitacionalé computada pela interação entre uma casca e todas as demais [19]: 2. Demonstre todos os passos intermediários para a dedução dos espectros para a CLC e CLE com intermitência.…”

“…Uma idéia seria avaliar o espectro de energia para vários redshifts [53] (é uma maneira de como os astrofísicos avaliam a idade do universo). Esta foi a avalição realizada por Caretta et al [19]. Contudo, ao invés de avaliar o espectro de energia cinética turbulenta de dados da astronomia observacional, a análise foi realizada com dados simulados pelo modelo Λ-CDM, através do cálculo do espectro energia potencial gravitacional, em função do inverso de um raio de percolação.…”

A new gravitational N-body simulation algorithm for investigation of cosmological chaotic advection

“…The gravitational N-body simulations have become a powerful tool for testing the theories of structure formation in astrophysical and cosmological systems [1]. In particular, it has been shown that the statistical characterization of dark matter distribution is an important ingredient in the investigation of large-scale structure formation in the Hubble volume simulated from the GADGET-VC algorithm [2].…”