Related papers: Void Formation: Does the Void-in-Cloud Process Mat…
We analyse the clustering of cosmic voids using a numerical simulation and the main galaxy sample from the Sloan Digital Sky Survey. We take into account the classification of voids into two types that resemble different evolutionary modes:…
The effects of particle discreteness in N-body simulations of Lambda Cold Dark Matter (LambdaCDM) are still an intensively debated issue. In this paper we explore such effects, taking into account the scatter caused by the randomness of the…
Cosmic voids in the large-scale structure of the Universe affect the peculiar motions of objects in their vicinity. Although these motions are difficult to observe directly, the clustering pattern of their surrounding tracers in redshift…
We test a theoretical description of the void size distribution function against direct estimates from halo catalogues of the DEMNUni suite of large cosmological simulations. Besides standard $\Lambda$CDM, we consider deviations of the dark…
We present catalogues of voids for the SDSS DR7 redshift survey and for Millennium I simulation mock data. We aim to compare the observations with simulations based on a $\Lambda$CDM model and a semi-analytic galaxy formation model. We use…
We present a simple empirical function for the average density profile of cosmic voids, identified via the watershed technique in $\Lambda$CDM N-body simulations. This function is universal across void size and redshift, accurately…
We use the void probability function to compare the redshift--space galaxy distribution in the Perseus--Pisces survey with artificial samples from N-body simulations of standard cold dark matter (CDM) and broken scale invariance (BSI)…
We use simulations of the formation and evolution of the galaxy population in the Local Universe to address the issue of whether the standard theoretical model succeeds in producing empty regions as large and as dark as the observed nearby…
The formalism by Press and Schechter (PS) is often used to infer number densities of virialized objects of mass M (e.g. quasars, galaxies, clusters of galaxies, etc.) from a count of initially overdense regions in a Gaussian density…
Cosmic voids are becoming key players in testing the physics of our Universe. Here we concentrate on the abundances and the dynamics of voids as these are among the best candidates to provide information on cosmological parameters. Cai,…
We use the Voids-within-Voids-within-Voids (VVV) simulations, a suite of successive nested N-body simulations with extremely high resolution (denoted, from low to high resolution, by L0 to L7), to test the Press-Schechter (PS), Sheth-Tormen…
Despite a history that dates back at least a quarter of a century studies of voids in the large--scale structure of the Universe are bedevilled by a major problem: there exist a large number of quite different void--finding algorithms, a…
We develop models of void formation starting from a small initial fluctuation at recombination and growing to a realistic present day density profile in agreement with observations of voids. The model construction is an extension of…
Using high-resolution simulations within the Cold and Warm Dark Matter models we study the evolution of small scale structure in the Local Volume, a sphere of 8 Mpc radius around the Local Group. We compare the observed spectrum of…
We discuss bulk viscous cosmological models. Since the bulk viscous pressure is negative, viable viscous cosmological scenarios with late time accelerated expansion can in principle be constructed. After discussing some alternative models…
We offer an exact analytical equation for the void central region. We show that the central density is solely determined by the amplitude of the initial perturbation. Our results suggest that N-body simulations somewhat overestimate the…
We present a model for the distribution of void sizes and its evolution in the context of hierarchical scenarios of gravitational structure formation. We find that at any cosmic epoch the voids have a size distribution which is well-peaked…
We extend earlier work on the problem of estimating the void-volume function -- the abundance and evolution of large voids which grow gravitationally in an expanding universe -- in two ways. The first removes an ambiguity about how the…
Cosmic voids are the major volume component in the matter distribution of the Universe. They posses great potential for constraining dark energy as well as for testing theories of gravity. Nevertheless, in spite of their growing popularity…
We present a comparison of the properties of galaxies in the most underdense regions of the Universe, where the galaxy number density is less than 10% of the mean density, with galaxies from more typical regions. We have compiled a sample…