中文
相关论文

相关论文: Dynamics of classes of barotropic fluids in spatia…

200 篇论文

We consider volume-preserving flows $(\Phi^f_t)_{t\in\mathbb{R}}$ on $S\times \mathbb{R}$, where $S$ is a closed connected surface of genus $g\geq 2$ and $(\Phi^f_t)_{t\in\mathbb{R}}$ has the form $\Phi^f_t(x,y)=(\phi_tx,y+\int_0^t…

动力系统 · 数学 2014-05-13 Krzysztof Fraczek , Corinna Ulcigrai

Using the dynamical system theory we show that the Friedmann-Robertson-Walker (FRW) cosmological model with bulk viscous fluid in the presence of cosmological constant is equivalent to a degenerate two dimensional Bogdanov-Takens normal…

广义相对论与量子宇宙学 · 物理学 2020-10-19 Asmaa Abdel Azim , Adel Awad , E. I. Lashin

For a perfect fluid, pressure $p$ and energy density $\rho$ are related via the equation of state (EOS) $\omega = p/\rho$, where $\omega$ is the EOS parameter, being its interpretation usually constrained to a numerical value for each…

We revisit the evolution of the scale factor in a flat FRW spacetime with a new generalized decay rule for the dynamic $\Lambda$-term under modified theories of gravity. It analyses certain cosmological parameters and examines their…

综合物理 · 物理学 2021-08-02 Anirudh Pradhan , De Avik , Tee How Loo , D. C. Maurya

We present a Friedmann-Robertson-Walker (FRW) quantum cosmological model within the framework of Finslerian geometry. In this work, we consider a specific fluid. We obtain the corresponding Wheeler-DeWitt equation as the usual constraint…

综合物理 · 物理学 2019-11-04 S S De , Farook Rahaman , Nupur Paul

In this work a new non-minimally coupled model is presented, where a generic function $f(R)$ of the scalar curvature factors the usual Einstein-Hilbert action functional, motivated by relevant results obtained from similar models. Its…

广义相对论与量子宇宙学 · 物理学 2016-11-22 R. P. L. Azevedo , J. Páramos

A grand unified field $\mathcal{M}^{\mu\nu}$ is constructed from Maxwell's Field tensor and appropriately modified flow field, both non-minimally coupled to gravity, to analyze the dynamics of hot charged fluids in curved background…

广义相对论与量子宇宙学 · 物理学 2015-06-23 Chinmoy Bhattacharjee , Rupam Das , S. M. Mahajan

Various models are under consideration with metric type flat FRW whose energy-momentum tensor is described by a perfect fluid whose generic equation state and taking into account the conservation principle, but considering some of the…

综合物理 · 物理学 2007-05-23 J. A. Belinchon

We investigate cosmological dynamics based on $f(R)$ gravity in the Palatini formulation. In this study we use the dynamical system methods. We show that the evolution of the Friedmann equation reduces to the form of the piece-wise smooth…

广义相对论与量子宇宙学 · 物理学 2018-05-30 Marek Szydlowski , Aleksander Stachowski

We study the tensorial modes of the two-fluid model, where one of this fluids has an equation of state $p = - \rho/3$ (variable cosmological constant, cosmic string fluid, texture) or $p = - \rho$ (cosmological constant), while the other…

广义相对论与量子宇宙学 · 物理学 2007-05-23 J. C. Fabris , S. V. B. Goncalves

In this paper we develop two models for the steady states and evolution of two dimensional isothermal self gravitating and rotating incompressible gas which are based on the hydrodynamic equations for stratified fluid. The first model is…

地球与行星天体物理 · 物理学 2015-04-14 Mayer Humi , Zilu Tian

We investigate the phase space dynamics of a bulk viscosity model in the Eckart approach for a spatially flat Friedmann-Robertson-Walker universe. We have included two barotropic fluids and a dark energy component. One of the barotropic…

广义相对论与量子宇宙学 · 物理学 2014-10-29 Norman Cruz , Samuel Lepe , Yoelsy Leyva , Francisco Peña , Joel Saavedra

The interplay between quantum fluctuation and spacetime curvature is shown to induce an additional quantum-curvature (QC) term in the energy-momentum tensor of fluid using the generalized framework of the stochastic variational method…

量子物理 · 物理学 2019-07-17 T. Koide , T. Kodama

The kinetic energy of barotropic flow coupled to an infnitely massive rotating sphere by an unresolved complex torque mechanism is approximated by a discrete spin-lattice model of fluid vorticity on a rotating sphere, analogous to a…

统计力学 · 物理学 2009-11-11 Chjan C. Lim , R. Singh Mavi

Nonlinear waves in defocusing media are investigated in the framework of the hydrodynamic description of light as a photon fluid. The observations are interpreted in terms of an emergent curved spacetime generated by the waves themselves,…

广义相对论与量子宇宙学 · 物理学 2015-12-07 Francesco Marino , Calum Maitland , David Vocke , Antonello Ortolan , Daniele Faccio

This paper provides an analytical examination of non-radial geodesics within the context of the spatially flat Friedmann Lema\^itre Robertson Walker (FLRW) spacetime. Using the symmetry properties of the system, two constants of motion…

广义相对论与量子宇宙学 · 物理学 2024-02-13 Omar Nemoul , Hichem Guergouri , Jamal Mimouni

We study the evolution of scalar cosmological perturbations in the (1+3)- covariant gauge-invariant formalism for generic $f(R)$ theories of gravity. Extending previous works, we give a complete set of equations describing the evolution of…

广义相对论与量子宇宙学 · 物理学 2012-06-08 Amare Abebe , Mohamed Abdelwahab , Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby

In this paper we performed investigation of the spatially-flat cosmological models whose spatial section is product of three- ("our Universe") and extra-dimensional parts. The matter source chosen to be the perfect fluid which exists in the…

广义相对论与量子宇宙学 · 物理学 2019-02-11 Sergey A. Pavluchenko

Present investigation devoted to the dynamical study of Relativistic Hydrodynamics with some thermodynamical characteristics in $f(R,G)$ gravity towards spatially homogeneous isotropic cosmological model filled with isotropic fluid. We…

综合物理 · 物理学 2020-04-09 S. H. Shekh , Simran Arora , V. R. Chirde , P. K. Sahoo

We consider an isothermal compressible fluid evolving on a cosmological background which may be either expanding or contracting toward the future. The Euler equations governing such a flow consist of two nonlinear hyperbolic balance laws…

偏微分方程分析 · 数学 2022-10-12 Yangyang Cao , Mohammad A. Ghazizadeh , Philippe G. LeFloch