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Perturbative Quantum Chromodynamics (pQCD) corrections and color superconductivity predict that strongly interacting matter can reveal new physical phenomena under extreme conditions. Taking into account these interaction effects, we…

General Relativity and Quantum Cosmology · Physics 2023-12-15 Juan M. Z. Pretel , Takol Tangphati , Ayan Banerjee , Anirudh Pradhan

We introduce a new type of generating theorems in General Relativity for anisotropic, static, spherically symmetric solutions of the Einstein field equations. The results are used to derive a class of solutions that can serve as new models…

General Relativity and Quantum Cosmology · Physics 2026-04-14 Paulo Luz , Sante Carloni

In this manuscript, we investigate the oscillatory behaviour of the anisotropy in the diagonal Bianchi-I spacetimes. Our starting point is a simplification of Einstein's equations using only observable or physical variables. As a…

General Relativity and Quantum Cosmology · Physics 2021-04-02 Leandro G Gomes , Bruno B. Bizarria , Gabriel A. de Souza Silva , William O. Clavijo

The dynamics of cosmological models with isotropic matter sources (perfect fluids) is extensively studied in the literature; in comparison, the dynamics of cosmological models with anisotropic matter sources is not. In this paper we…

General Relativity and Quantum Cosmology · Physics 2011-02-16 Simone Calogero , J. Mark Heinzle

We study the dynamics of spatially homogeneous and isotropic spacetimes containing a fluid undergoing microscopic velocity diffusion in a cosmological scalar field. After deriving a few exact solutions of the equations, we continue by…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Artur Alho , Simone Calogero , Maria P. Machado Ramos , Ana J. Soares

We study the consequences of a homogeneous dark energy fluid having a non-vanishing velocity with respect to the matter and radiation large-scale rest frames. We consider homogeneous anisotropic cosmological models with four fluids…

Astrophysics · Physics 2008-11-26 Jose Beltran Jimenez , Antonio L. Maroto

We study the cosmological Burgers model, as we call it, which is a nonlinear hyperbolic balance law (in one and two spatial variables) posed on an expanding or contracting background. We design a finite volume scheme that is fourth-order in…

Analysis of PDEs · Mathematics 2019-11-19 Yangyang Cao , Mohammad A. Ghazizadeh , Philippe G. LeFloch

In this paper, we investigate the exact solution of an anisotropic space-time in the context of $f(Q)$ gravity, where $f\left( Q\right) $ is the arbitrary function of the non-metricity scalar $Q$. Here, we consider a specific power-law form…

General Relativity and Quantum Cosmology · Physics 2022-12-01 M. Koussour , M. Bennai

In our study, we explored the properties of a spatially homogeneous and anisotropic Bianchi type V I0 Universe. Our investigation centered on integrating cosmic domain walls into the f(R, T) theory of gravitation, initially proposed by…

General Relativity and Quantum Cosmology · Physics 2024-03-05 V. R. Patil , J. L. Pawde , R. V. Mapari , S. K. Waghmare

In this paper we investigate the constant volume exponential solutions (i.e. the solutions with the scale factors change exponentially over time so that the comoving volume remains the same) in the Einstein-Gauss-Bonnet gravity. We find…

General Relativity and Quantum Cosmology · Physics 2014-12-17 Dmitry Chirkov , Sergey A. Pavluchenko , Alexey Toporensky

The goal of this work is to develop physical models for spherically symmetric systems in the realm of $f(Q)$ gravity. The field equations are set up for anisotropic fluid and formulate these equations using physical ansatz of Vaidya-Tikekar…

General Relativity and Quantum Cosmology · Physics 2025-03-28 M. Awais , M. Azam

In this article we perform a detailed theoretical analysis for a class of new exact solutions with anisotropic fluid distribution of matter for compact objects in hydrostatic equilibrium. To achieve this we call the relation between the…

General Relativity and Quantum Cosmology · Physics 2018-05-10 S. K. Maurya , Ayan Banerjee , Phongpichit Channuie

Under the premise that the current observations of the cosmic microwave background radiation set a very stringent limit to the anisotropy of the universe, we consider an anistropic model in the presence of a barotropic perfect fluid and a…

General Relativity and Quantum Cosmology · Physics 2020-06-02 J. Socorro , S. Pérez-Payán , Abraham Espinoza-García , Luis Rey Díaz-Barrón

This paper presents a class of exact spherical symmetric solutions of the Einstein equations admitting heat-conducting anisotropic fluid as a collapsing matter. The exterior spacetime is assumed to be the Vaidya metric. This class of…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Suresh C. Jaryal

An isotropic and homogeneous cosmological model with a source of dark energy is studied. That source is simulated with a viscous relativistic fluid with minimal causal correction. In this model the restrictions on the parameters coming from…

General Relativity and Quantum Cosmology · Physics 2017-04-20 Carlos E. Laciana

It is shown that unlike the perfect fluid case, anisotropic fluids (principal stresses unequal) may be geodesic, without this implying the vanishing of (spatial) pressure gradients. Then the condition of vanishing four acceleration is…

General Relativity and Quantum Cosmology · Physics 2009-11-07 L. Herrera , J. Martin , J. Ospino

We use spherical coordinates to devise a new exact solution to the governing equations of geophysical fluid dynamics for an inviscid and incompressible fluid with a general density distribution and subjected to forcing terms. The latter are…

Fluid Dynamics · Physics 2020-10-20 Calin Iulian Martin , Ronald Quirchmayr

We consider a self-consistent system of Bianchi type-I (BI) gravitational field and a binary mixture of perfect fluid and dark energy. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., $p = \zeta \ve$, with…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha

In this article, we present a class of relativistic solutions describing spherically symmetric and static anisotropic stars in hydrostatic equilibrium. For this purpose, we consider a particularized matric potential, namely, Buchdahl ansatz…

General Relativity and Quantum Cosmology · Physics 2021-08-03 S. K. Maurya , Ayan Banerjee , M. K. Jasim , J. Kumar , A. K. Prasad , Anirudh Pradhan

This paper constructs two immediate extensions of the existing anisotropic solutions in the context of Einstein-Maxwell framework by employing minimal geometric deformation. To achieve this, we assume a static spherical interior initially…

General Relativity and Quantum Cosmology · Physics 2023-10-03 M. Sharif , Tayyab Naseer