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Related papers: Structure formation in the quasispherical Szekeres…

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We present an investigations on the influence of dynamical quintessence field models on the formation of non-linear structures. In particular, we focus on the structure traced by the mass function. Our contribution builds on previous…

Astrophysics · Physics 2009-11-11 Morgan Le Delliou

We investigate the influence of a shear flow on the process of nucleation. Mesoscopic nonequilibrium thermodynamics is used to derive the Fokker-Planck equation governing the evolution of the cluster size distribution in a metastable phase…

Statistical Mechanics · Physics 2009-11-10 D. Reguera , J. M. Rubi

The formation and evolution of the cosmic web in which galaxy superclusters are the largest relatively isolated objects is governed by a gravitational attraction of dark matter and antigravity of dark energy (cosmological constant). We…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-23 Mirt Gramann , Maret Einasto , Pekka Heinämäki , Pekka Teerikorpi , Enn Saar , Pasi Nurmi , Jaan Einasto

Shear-flow-induced structure formation in surfactant-water mixtures is investigated numerically using a meshless-membrane model in combination with a particle-based hydrodynamics simulation approach for the solvent. At low shear rates,…

Soft Condensed Matter · Physics 2013-07-02 Hayato Shiba , Hiroshi Noguchi , Gerhard Gompper

Observations of the expansion rate of the universe at late times disagree by a factor of 1.5-2 with the prediction of homogeneous and isotropic models based on ordinary matter and gravity. We discuss how the departure from linearly…

Astrophysics · Physics 2009-03-17 Syksy Rasanen

We investigate the evolution of non-linear density perturbations by taking into account the effects of deviations from spherical symmetry of a system. Starting from the standard spherical top hat model in which these effects are ignored, we…

Astrophysics · Physics 2009-10-31 S. Engineer , Nissim Kanekar , T. Padmanabhan

Using two dimensional simulations, we study the formation of structures with a high-density contrast by magnetohydrodynamic waves in regions in which the ratio of thermal to magnetic pressure is small. The initial state is a uniform…

Astrophysics · Physics 2009-11-11 S. Van Loo , S. A. E. G. Falle , T. W. Hartquist

We investigate the liquid state structure of the two-dimensional (2D) model introduced by Barkan et al. [Phys. Rev. Lett. 113, 098304 (2014)], which exhibits quasicrystalline and other unusual solid phases, focussing on the radial…

Soft Condensed Matter · Physics 2018-09-03 M. C. Walters , P. Subramanian , A. J. Archer , R. Evans

We study the occurrence, visibility, and curvature strength of singularities in dust-containing Szekeres spacetimes (which possess no Killing vectors) with a positive cosmological constant. We find that such singularities can be locally…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergio M. C. V. Goncalves

We study effects of inhomogeneities on distance measures in an exact relativistic Swiss-cheese model of the universe, focusing on the distance modulus. The model has LCDM background dynamics, and the `holes' are non-symmetric structures…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-07 Austin Peel , M. A. Troxel , Mustapha Ishak

It is shown: 1) that in two-dimensional, incompressible, viscous flows the vorticity-area distribution evolves according to an advection-diffusion equation with a negative, time dependent diffusion coefficient and 2) how to use the…

chao-dyn · Physics 2009-10-31 H. W. Capel , R. A. Pasmanter

We study analytically the possibility that mergers of haloes are more highly clustered than the general population of haloes of comparable masses. We begin by investigating predictions for merger bias within the extended Press-Schechter…

Astrophysics · Physics 2009-11-11 Steven R. Furlanetto , Marc Kamionkowski

We study the occurrence and nature of naked singularities for a dust model with non-zero cosmological constant in ($n+2$)-dimensional Szekeres space-times (which possess no Killing vectors) for $n\geq 2$. We find that central shell-focusing…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ujjal Debnath , Subenoy Chakraborty , John D. Barrow

The majority of bright distant quasars $(z {}^{>}_{\sim} 1)$ may form in massive mergers appearing in compact galaxy groups in/and young clusters. The expected tests are (i) large correlation signal for medium-$z$ QSOs $(1 < z < 2)$ and…

Astrophysics · Physics 2009-10-28 V. N. Lukash

The purpose of the present work is based on two main observations: the tensions encountered by the standard $\Lambda$CDM model when confronted to precision small scale cosmological data and the finding that the matter distribution and the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-20 Marie-Noëlle Célérier

We study the spatial patterns formed by a system of interacting particles where the mobility of any individual is determined by the population crowding at two different spatial scales. In this way we model the behavior of some biological…

Statistical Mechanics · Physics 2015-07-08 Ricardo Martínez-García , Clara Murgui , Emilio Hernández-García , Cristóbal López

An asymptotic interface equation for directional solidification near the absolute stabiliy limit is extended by a nonlocal term describing a shear flow parallel to the interface. In the long-wave limit considered, the flow acts…

Condensed Matter · Physics 2009-11-07 Yannick Marietti , Jean-Marc Debierre , Thomas-Michael Bock , Klaus Kassner

The local Universe displays a rich hierarchical pattern of galaxy clusters and superclusters. The early Universe, however, was almost smooth, with only slight 'ripples' seen in the cosmic microwave background radiation. Models of the…

Astrophysics · Physics 2009-10-31 Peter Coles , Lung-Yih Chiang

It has recently been shown that identical, isotropic particles can form complex crystals and quasicrystals. In order to understand the relation between the particle interaction and the structure, which it stabilizes, the phase behavior of a…

Materials Science · Physics 2009-04-01 Michael Engel , Hans-Rainer Trebin

We examine a novel class of toy models of cosmological inhomogeneities by smoothly matching along a suitable hypersurface an arbitrary number of sections of "quasi flat" inhomogeous and anisotropic Szekeres-II models to sections of any…

General Relativity and Quantum Cosmology · Physics 2021-04-14 Sebastián Nájera , Roberto A. Sussman