They found that primordial tidal fields play an important role in the evolution of structure, thus the dominant elements are filaments, not flat pancakes.īond et al. (1996) studied in detail the formation of the large-scale structure. One problem remained: both numerical simulations and direct observations suggested that the dominant structural elements of the cosmic web are filaments of various scales, whereas the classical Zeldovich (1970) scenario predicted the formation of flat pancake-like systems. An even closer agreement of simulations with observations is obtained in models with a cosmological constant, ΛCDM, as demonstrated by Gramann (1988). The comparison of simulations for both dark matter types demonstrated the advantages of the CDM model – in this model, the fine structure is present in the form of filaments of various scales (see Melott et al. The basic difference between the HDM and CDM scenarios is the absence or presence of small-scale density fluctuations. The problem of the absence of the fine structure was solved when the cold dark matter (CDM) scenario was suggested by Bond et al. The simulations performed for the neutrino-dominated universe, called the hot dark matter (HDM) model ( White et al. In the real world, the most common structural elements were filaments of galaxies and their clusters, whereas the Zeldovich (1978) scenario predicted the formation of flat formless pancake-like systems (for a discussion see Zeldovich et al. However, there were some important differences between the models and the observations. This observational picture was rather similar to the theoretical prediction of Zeldovich (1970), the so-called pancake scenario of galaxy formation, as discussed by Zeldovich (1978). The first studies of the three-dimensional distribution of galaxies and clusters of galaxies demonstrated that they are not distributed randomly, but are mostly located in filamentary superclusters connected by galaxy filaments to form a connected network, leaving large regions devoid of galaxies ( Gregory & Thompson 1978 Jõeveer & Einasto 1978 Jõeveer et al. Key words: large-scale structure of Universe / cosmology: miscellaneous / cosmology: theory / galaxies: clusters: general / dark matter / methods: numerical Larger perturbations do not change the texture of the web, but modulate the richness of galaxy systems, and make voids emptier. We conclude that the texture of the cosmic web is determined by density perturbations of the scales up to ~ 100 h -1 Mpc. Filaments of galaxies and clusters are created by perturbations of intermediate scale from ~ 8 to ~ 32 h -1 Mpc, and superclusters of galaxies by larger perturbations.Ĭonclusions. Our analysis shows that the fine structure (groups and clusters of galaxies) are created by small-scale density perturbations of scale ≤ 8 h -1 Mpc. We analyse the density field and study void sizes and density field clusters in different models. In addition, we have one model, where we cut the intermediate waves. We perform numerical simulations with the full power spectrum of perturbations, and with a spectrum cut at long wavelengths. Our goal is to understand the role of density perturbations on various scales in the formation and evolution of the cosmic web. We follow the evolution of galaxy systems in numerical simulations. Research Center for the Early Universe (RESCEU), Graduate School of Science, The University of Tokyo, Tokyo 113-0033, JapanĪims. Landau Institute for Theoretical Physics, Moscow 119334, Russia ICRANet, Piazza della Repubblica 10, 65122 Pescara, ItalyĪstrophysical Institute Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany Tartu Observatory, 61602 Tõravere, EstoniaĮ-mail: Academy of Sciences, 10130 Tallinn, Estonia Astronomical objects: linking to databases.Including author names using non-Roman alphabets.Suggested resources for more tips on language editing in the sciences Punctuation and style concerns regarding equations, figures, tables, and footnotes
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