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The kinetic approach to the formation of the filaments in the large-scale matter distribution in the Universe is considered within the Vlasov formalism. The structures arise due to the self-consistent dynamics, along with the repulsive term…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 V. G. Gurzadyan , N. N. Fimin , V. M. Chechetkin

We investigate the cosmological applications of fluids having an equation of state which is the analog to the one related to the isotropic deformation of crystalline solids, that is containing logarithmic terms of the energy density,…

General Relativity and Quantum Cosmology · Physics 2018-11-14 S. D. Odintsov , V. K. Oikonomou , A. V. Timoshkin , Emmanuel N. Saridakis , R. Myrzakulov

A detailed derivation of the Lattice Boltzmann (LB) scheme for relativistic fluids recently proposed in Ref. [1], is presented. The method is numerically validated and applied to the case of two quite different relativistic fluid dynamic…

Solar and Stellar Astrophysics · Physics 2010-12-28 M. Mendoza , B. M. Boghosian , H. J. Herrmann , S. Succi

In this first paper we present a Lagrangian framework for the description of structure formation in general relativity, restricting attention to irrotational dust matter. As an application we present a self-contained derivation of a…

General Relativity and Quantum Cosmology · Physics 2012-07-24 Thomas Buchert , Matthias Ostermann

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

We present a dynamic subspace approach for efficiently approximating large-scale systems by learning time-continuous trajectories on the Grassmannian manifold. By parameterizing a low-dimensional basis as a geodesic path, the method allows…

Numerical Analysis · Mathematics 2026-05-26 Jack DeChant , Rudy Geelen , Shane A. McQuarrie , Johann Guilleminot

We show that the recently constructed holographic duals of conformal non-relativistic theories behave hydrodynamically at long distances, and construct the gravitational dual of fluid flows in a long-wavelength approximation. We compute the…

High Energy Physics - Theory · Physics 2009-02-02 Mukund Rangamani , Simon F. Ross , D. T. Son , Ethan G. Thompson

We study the classical and quantum models of a Friedmann-Robertson-Walker (FRW) cosmology, coupled to a perfect fluid, in the context of the scalar-metric gravity. Using the Schutz' representation for the perfect fluid, we show that, under…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Babak Vakili

This paper shows that in second-order hyperbolic systems of partial differential equations proposed in authors' earlier paper (J. Math. Phys. 59 (2018)) for modelling the relativistic dynamics of barotropic fluids in the presence of…

Analysis of PDEs · Mathematics 2023-03-22 Heinrich Freistuhler

We consider a non-isothermal compositional gas liquid model for the simulation of well operations in geothermal processes. The model accounts for phase transitions assumed to be at thermodynamical equilibrium and is based on an…

Numerical Analysis · Mathematics 2024-01-05 Daniel Castanon Quiroz , Laurent Jeannin , Simon Lopez , Roland Masson

We analyze dynamics of the FRW models with global rotation in terms of dynamical system methods. We reduce dynamics of these models to the FRW models with some fictitious fluid which scales like radiation matter. This fluid mimics…

Astrophysics · Physics 2009-11-10 Wlodzimierz Godlowski , Marek Szydlowski

The aim of this set of lectures is a systematic presentation of a 1+3 covariant approach to studying the geometry, dynamics, and observational properties of relativistic cosmological models. In giving (i) the basic 1+3 covariant relations…

General Relativity and Quantum Cosmology · Physics 2008-11-26 George F R Ellis , Henk van Elst

We discuss dynamical systems approaches and methods applied to flat Robertson-Walker models in $f(R)$-gravity. We argue that a complete description of the solution space of a model requires a global state space analysis that motivates…

General Relativity and Quantum Cosmology · Physics 2016-09-07 Artur Alho , Sante Carloni , Claes Uggla

The topology of large scale structure is studied as a function of galaxy type using the genus statistic. In hydrodynamical cosmological CDM simulations, galaxies form on caustic surfaces (Zeldovich pancakes) then slowly drain onto filaments…

Astrophysics · Physics 2012-08-27 J. Richard Gott , III , Renyue Cen , Jeremiah P. Ostriker

We study a gravitating spherically symmetric nonrelativistic configuration consisting of a spinor fluid whose effective equation of state is derived from a consideration of a limiting system supported by a massive nonlinear spinor field.…

General Relativity and Quantum Cosmology · Physics 2021-06-17 Vladimir Dzhunushaliev , Vladimir Folomeev

We extend the general relativistic Lagrangian perturbation theory, recently developed for the formation of cosmic structures in a dust continuum, to the case of model universes containing a single fluid with a single-valued analytic…

General Relativity and Quantum Cosmology · Physics 2018-08-10 Yong-Zhuang Li , Pierre Mourier , Thomas Buchert , David L. Wiltshire

These lecture notes introduce analytical tools, methods and results describing the growth of cosmological structure beyond the linear regime. The presentation is focused on the single flow regime of the Vlasov-Poisson equation describing…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 Francis Bernardeau

In this study, we introduce an extension of the quasi-dilaton massive gravity theory and derive the field equations by varying the action with respect to the metric. This extension elucidates the dynamics of the system and demonstrates how…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Sobhan Kazempour , Amin Rezaei Akbarieh , Sichun Sun , Chengye Yu

The intrinsic geometric properties of generalized Darboux-Manakov-Zakharov systems of semilinear partial differential equations \label{GDMZabstract} \frac{\partial^2 u}{\partial x_i\partial x_j}=f_{ij}\Big(x_k,u,\frac{\partial u}{\partial…

Differential Geometry · Mathematics 2010-02-08 Peter J. Vassiliou

Cosmological simulations are powerful tools in the context of structure formation. They allow us to explore the assembly and clustering of dark matter halos, to validate or reject possible scenarios of structure formation, and to…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-12 Milena Valentini , Klaus Dolag
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