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Related papers: Complexity in cosmic structures

200 papers

I consider the growth of inhomogeneities in a low-density baryonic, vacuum energy-dominated universe in the context of modified Newtonian dynamics (MOND). I first write down a two-field Langrangian-based theory of MOND (non-relativistic),…

Astrophysics · Physics 2009-10-31 R. H. Sanders

We examine from first principles one of the basic assumptions of modern quantum theories of structure formation in the early universe, i.e., the conditions upon which fluctuations of a quantum field may transmute into classical stochastic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. Calzetta , B. L. Hu

Galaxies are not uniformly distributed in space. On large scales the Universe displays coherent structure, with galaxies residing in groups and clusters on scales of ~1-3 Mpc/h, which lie at the intersections of long filaments of galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Alison L. Coil

A standard method to study the mass distribution in galaxy clusters is through strong lensing of background galaxies in which the positions of multiple images of the same source constrain the surface mass distribution of the cluster.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-26 Ole Host

We present a new cosmological model, based on the holographic principle, which shares many of the virtues of inflation. The very earliest semiclassical era of the universe is dominated by a dense gas of black holes, with equation of state…

High Energy Physics - Theory · Physics 2007-05-23 T. Banks , W. Fischler

We propose a phenomenological generalization of the models of large-scale structure formation in the Universe by gravitational instability in two ways: we include pressure forces to model multi-streaming, and noise to model fluctuations due…

Astrophysics · Physics 2011-05-23 Thomas Buchert , Alvaro Dominguez , Juan Perez-Mercader

While the universe becomes more and more homogeneous at large scales, statistical analysis of galaxy catalogs have revealed a fractal structure at small-scales (\lambda < 100 h^{-1} Mpc), with a fractal dimension D=1.5-2 (Sylos Labini et al…

Astrophysics · Physics 2010-11-30 H. J. de Vega , N. Sánchez , F. Combes

A calculation of the one-mode occupation numbers for vacuum fluctuations of massive fields in De Sitter space shows that their use for the generation of classical density perturbations in inflationary cosmology very much depends on their…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Milan Mijic

We discuss the Buchert equations, which describe the average expansion of an inhomogeneous dust universe. In the limit of small perturbations, they reduce to the Friedmann-Robertson-Walker equations. However, when the universe is very…

Astrophysics · Physics 2008-11-26 Syksy Rasanen

If one wants to represent the galaxy number density at some point in terms of only the mass density at the same point, there appears the stochasticity in such a relation, which is referred to as ``stochastic bias''. The stochasticity is…

Astrophysics · Physics 2009-10-31 Takahiko Matsubara

Structure occurs over a vast range of scales in the universe. Our large-scale cosmological models are coarse-grained representations of what exists, which have much less structure than there really is. An important problem for cosmology is…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-05 Chris Clarkson , George Ellis , Julien Larena , Obinna Umeh

We present results for the cosmic non-linear density-fluctuation power spectrum based on the analytical formalism developed in [1] which allows us to study cosmic structure formation based on Newtonian particle dynamics in phase-space. This…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Tristan Daus , Elena Kozlikin

By means of high-resolution N-body simulations in a LambdaCDM cosmology, we verify that scaling relations similar to those observed for nearby galaxy clusters are also defined by their dark matter hosts; the slopes, however, are not the…

Astrophysics · Physics 2016-03-23 B. Lanzoni , L. Ciotti , A. Cappi , G. Tormen , G. Zamorani

By virtue of their high galaxy space densities and their large spatial separations, clusters are efficient and accurate tracers of the large-scale density and velocity fields. Substantial progress has been made over the past decade in the…

Astrophysics · Physics 2007-05-23 Marc Postman

We present a general description of the scalar field dark matter (SFDM) hypothesis in the cosmological context. The scenario of structure formation under such a hypothesis is based on Jeans instabilities of fluctuations of the scalar field.…

Universe structure emerges in the unreduced, complex-dynamical interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis avoiding any perturbative model gives…

General Physics · Physics 2015-03-20 Andrei P. Kirilyuk

Using the initial peculiar velocity field, we analytically study the hierarchical formation of gravitationally bound objects. The field is smoothed over a scale that corresponds to the mass of a given class of objects. Through the…

Astrophysics · Physics 2008-11-26 H. Mouri , Y. Taniguchi

Universe structure emerges in the unreduced, complex-dynamic interaction process with the simplest initial configuration (two attracting homogeneous fields, quant-ph/9902015). The unreduced interaction analysis gives intrinsically creative…

General Physics · Physics 2007-05-23 Andrei P. Kirilyuk

Observational cosmology is in its "golden age" with a vast amount of recent data on the distribution of matter and light in the universe. This data can be used to probe theories of the very early universe. It is small amplitude cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Robert H. Brandenberger

In a series of three papers, we introduced a novel cluster formation model that describes the formation, growth, and disruption of star clusters in high-resolution cosmological simulations. We tested this model on a Milky Way-sized galaxy…

Astrophysics of Galaxies · Physics 2020-03-18 Hui Li , Oleg Gnedin