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Related papers: Coupled fluids model in FRW space-time

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Two-scale models pose a promising approach in simulating reactive flow and transport in evolving porous media. Classically, homogenized flow and transport equations are solved on the macroscopic scale, while effective parameters are…

Analysis of PDEs · Mathematics 2022-02-01 Stephan Gärttner , Peter Knabner , Nadja Ray

The present work deals with homogeneous and isotropic FLRW model of the Universe having a system of non-interacting diffusive cosmic fluids with barotropic equation of state (constant or variable equation of state parameter). Due to…

General Relativity and Quantum Cosmology · Physics 2019-02-22 Subhayan Maity , Pritikana Bhandari , Subenoy Chakraborty

In this work, we study a particular system of coagulation equations characterized by two values, namely volume $v$ and surface area $a$. Compared to the standard one-dimensional models, this model incorporates additional information about…

Analysis of PDEs · Mathematics 2024-03-12 Iulia Cristian , Juan J. L. Velázquez

In adaptive resolution simulations, molecular fluids are modeled employing different levels of resolution in different subregions of the system. When traveling from one region to the other, particles change their resolution on the fly. One…

Statistical Mechanics · Physics 2015-10-28 Karsten Kreis , Aoife C. Fogarty , Kurt Kremer , Raffaello Potestio

In the framework of spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time, we investigate a two-fluid cosmological model where a tachyon scalar field with self-interacting potential and a modified chaplygin gas with…

General Relativity and Quantum Cosmology · Physics 2024-12-25 Goutam Mandal , Sujay Kr. Biswas

In this work we explore the consequences that a non-minimal coupling between geometry and matter can have on the dynamics of perfect fluids. It is argued that the presence of a static, axially symmetric pressureless fluid does not imply a…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Orfeu Bertolami , António Martins

Cosmological models with time dependent $\Lambda$ (read as $\Lambda (t)$) have been investigated widely in the literature. Models that solve background dynamics analytically, are of special interest. Additionally, the allowance of past or…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Supriya Pan

Solutions to flat space Friedmann-Robertson-Walker cosmologies in Brans-Dicke theory with a cosmological constant are investigated. The matter is modelled as a $\gamma$-law perfect fluid. The field equations are reduced from fourth order to…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Shawn J. Kolitch

We examine the dynamical implications of an interaction between some of the fluid components of the universe. We consider the combination of three matter components, one of which is a perfect fluid and the other two are interacting. The…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Ana Nunes , Jose P. Mimoso , Tiago C. Charters

The coupled quintessence model with disformal couplings is treated here to mimic the $\Lambda$CDM background. Using this approach, the quintessence potential does not have to be specified. The model considers a generic fluid coupled to the…

General Relativity and Quantum Cosmology · Physics 2021-03-16 Avishek Dusoye , Alvaro de la Cruz-Dombriz , Peter Dunsby , Nelson J. Nunes

We propose a two-fold approach to model reduction of fluid-structure interaction. The state equations for the fluid are solved with reduced basis methods. These are model reduction methods for parametric partial differential equations using…

Numerical Analysis · Mathematics 2010-05-20 Toni Lassila , Gianluigi Rozza

The Cardassian universe is a proposed modification to the Friedmann Robertson Walker (FRW) equation in which the universe is flat, matter dominated, and accelerating. Here we generalize the original Cardassian proposal to include additional…

High Energy Physics - Phenomenology · Physics 2010-12-09 Katherine Freese

Surface-subsurface flow models for hydrological applications solve a coupled multiphysics problem. This usually consists of some form of the Richards and shallow water equations. A typical setup couples these two nonlinear partial…

Numerical Analysis · Mathematics 2025-04-25 Valentina Schüller , Philipp Birken , Andreas Dedner

We examine the time evolution of the D=d+4 dimensional Einstein field equations subjected to a flat Robertson-Walker metric where the 3D and higher-dimensional scale factors are allowed to evolve at different rates. We find the exact…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Chad Middleton , Bret A. Brouse , Scott D. Jackson

We study the dynamics of the FLRW flat cosmological models in which the vacuum energy density varies with time, $\Lambda(t)$. In particular, we investigate the dynamical properties of a generalized vacuum model and we find that under…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Spyros Basilakos

We establish the future non-linear stability of Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) solutions to the Einstein-Euler equations of the universe filled with a large class of perfect fluids (the equations of state are allowed to be…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Chao Liu , Changhua Wei

In Friedman-Robertson-Walker flat spacetime, we consider a three fluid cosmological model which contains dark matter, dark energy and baryonic matter in the form of perfect fluid with a barotropic equation of state. Dark matter is taken in…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Nilanjana Mahata , Subenoy Chakraborty

We consider a non-minimal coupling of a perfect fluid matter system with geometry, which the coupling function is taken to be an arbitrary function of the Ricci scalar. Due to such a coupling, the matter stress tensor is no longer conserved…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Yousef Bisabr

Motivated by a semi-holographic approach to the dynamics of quark-gluon plasma which combines holographic and perturbative descriptions of a strongly coupled infrared and a more weakly coupled ultraviolet sector, we construct a hybrid…

High Energy Physics - Phenomenology · Physics 2018-08-29 Aleksi Kurkela , Ayan Mukhopadhyay , Florian Preis , Anton Rebhan , Alexander Soloviev

One of the key choices for numerical models of geophysical fluids is how parametrisations of physical processes interact with the numerical methods that handle the resolved flow, known in the atmospheric community as the dynamical core. As…

Numerical Analysis · Mathematics 2026-05-05 Nell Hartney , Thomas M. Bendall , Jemma Shipton