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Related papers: Structure formation in the Lemaitre-Tolman model

200 papers

The Lagrangian theory of structure formation in cosmological fluids, restricted to the matter model ``dust'', provides successful models of large-scale structure in the Universe in the laminar regime, i.e., where the fluid flow is…

Astrophysics · Physics 2011-05-23 Susanne Adler , Thomas Buchert

The aim of this paper is to provide an analytical model for the formation of stable structures (cosmological or astrophysical), where stability is obtained through the tangential pressure countering the effect of gravity. We utilize the…

General Relativity and Quantum Cosmology · Physics 2025-11-20 Jan J. Ostrowski

We perform numerical evolutions of cosmological scenarios using a standard general relativistic code in spherical symmetry. We concentrate on two different situations: initial matter distributions that are homogeneous and isotropic, and…

General Relativity and Quantum Cosmology · Physics 2014-12-09 Jose M. Torres , Miguel Alcubierre , Alberto Diez-Tejedor , Dario Nunez

Pattern formation in systems with a conserved quantity is considered by studying the appropriate amplitude equations. The conservation law leads to a large-scale neutral mode that must be included in the asymptotic analysis for pattern…

Pattern Formation and Solitons · Physics 2009-10-31 P. C. Matthews , S. M. Cox

We propose general conditions for the emergence of Turing patterns in a domain that changes size through homogeneous growth/shrinkage based on the qualitative changes of a potential function. For this part of the work, we consider the most…

Pattern Formation and Solitons · Physics 2023-10-03 Aldo Ledesma-Durán

Dynamical coherent structure (pattern) formation in the Klein-Gordon lattice excited by periodic external field near the optical resonance is studied. It is shown that besides spatial patterns discovered recently (V.M.Burlakov,…

patt-sol · Physics 2009-10-31 Victor M. Burlakov

We demonstrate the occurrence of permanent spikes using the Lemaitre-Tolman-Bondi models, chosen because the solutions are exact and can be analyzed by qualitative dynamical systems methods. Three examples are given and illustrated…

General Relativity and Quantum Cosmology · Physics 2014-05-22 Alan Coley , Woei Chet Lim

The standard theory of cosmic structure formation posits that the present-day rich structure of the Universe developed through gravitational amplification of tiny matter density fluctuations generated in its very early history. Recent…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-25 Naoki Yoshida

Segregation patterns of size-bidisperse particle mixtures in a fully-three-dimensional flow produced by alternately rotating a spherical tumbler about two perpendicular axes are studied over a range of particle sizes and volume ratios using…

Soft Condensed Matter · Physics 2019-07-03 Mengqi Yu , Paul B. Umbanhowar , Julio M. Ottino , Richard M. Lueptow

In recent years, unprecedented progress in observational cosmology has revealed a great deal of information about the formation and evolution of structures in the universe. This, in turn, has raised many challenging issues for the…

Astrophysics · Physics 2010-12-09 T. Roy Choudhury

Large scale density modes are difficult to measure because they are sensitive to systematic observational errors in galaxy surveys, but we can study them indirectly by observing their impact on small scale perturbations. Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-08 Peikai Li , Scott Dodelson , Rupert A. C. Croft

An approximate statistical description of the formation and evolution of structure of the universe based on the Zel'dovich theory of gravitational instability is proposed. It is found that the evolution of DM structure shows features of…

Astrophysics · Physics 2009-10-31 M. Demianski , A. Doroshkevich

This article is concerned with the stability and long-time dynamics of structures arising from a structureless state. The paradigm is suggested by developmental biology, where morphogenesis is thought to result from a competition between…

Pattern Formation and Solitons · Physics 2007-06-18 Hans G. Kaper , Shouhong Wang , Masoud Yari

The Riemann-Hilbert problem associated with the integrable PDE is used as a nonlinear transformation of the nearly integrable PDE to the spectral space. The temporal evolution of the spectral data is derived with account for arbitrary…

Exactly Solvable and Integrable Systems · Physics 2015-06-26 V. S. Shchesnovich

We, first, analytically work out the long-term, i.e. averaged over one orbital revolution, perturbations on the orbit of a test particle moving in a local Fermi frame induced therein by the cosmological tidal effects of the inhomogeneous…

General Relativity and Quantum Cosmology · Physics 2010-06-07 Lorenzo Iorio

A collection of thin structures buckle, bend, and bump into each-other when confined. This contact can lead to the formation of patterns: hair will self-organize in curls; DNA strands will layer into cell nuclei; paper, when crumpled, will…

Soft Condensed Matter · Physics 2023-04-19 Arman Guerra , Anja Slim , Douglas P. Holmes , Ousmane Kodio

The noise-induced pattern formation in a population dynamical model of three interacting species in the coexistence regime is investigated. A coupled map lattice of Lotka-Volterra equations in the presence of multiplicative noise is used to…

Statistical Mechanics · Physics 2007-05-23 A. Fiasconaro , D. Valenti , B. Spagnolo

We present a detailed parameter study of collapsing turbulent cloud cores, varying the initial density profile and the initial turbulent velocity field. We systematically investigate the influence of different initial conditions on the star…

Solar and Stellar Astrophysics · Physics 2015-05-19 Philipp Girichidis , Christoph Federrath , Robi Banerjee , Ralf S. Klessen

The concept of evolutionary development of structures constituted a \emph{real} revolution in biology: it was possible to understand how the very complex structures of life can arise in an out-of-equilibrium system. The investigation of…

Populations and Evolution · Quantitative Biology 2009-08-27 Franco Bagnoli

Our universe hosts various large-scale structures from voids to galaxy clusters, so it would be interesting to find some simple and reasonable measure to describe the inhomogeneities in the universe. We explore two different methods for…

General Relativity and Quantum Cosmology · Physics 2015-03-18 Nan Li , Xiao-Long Li , Shu-Peng Song