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Related papers: Anisotropic chiral cosmology: exact solutions

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In the context of brane cosmology, a scenario where our universe is a 3+1-dimensional surface (the ``brane'') embedded in a five-dimensional spacetime (the ``bulk''), we study geometries for which the brane is anisotropic - more…

High Energy Physics - Theory · Physics 2010-02-03 A. Fabbri , D. Langlois , D. A. Steer , R. Zegers

We show how the scalar field, a candidate of quintessence, in a proposed model of the scalar-tensor theories of gravity provides a way to understand a small but nonzero cosmological constant as indicated by recent observations. A particular…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Yasunori Fujii

We look for necessary conditions such that minimally coupled scalar-tensor theory with a massive scalar field and a perfect fluid in the Bianchi type I model isotropises. Then we derive the dynamical asymptotical properties of the Universe.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stephane Fay

We consider an anisotropic brane world with Bianchi type I and V geometries where the mechanism of confining the matter on the brane is through the use of a confining potential. The resulting equations on the anisotropic brane are modified…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Heydari-Fard , H. R. Sepangi

Inspired by an interesting counterexample to the cosmic no-hair conjecture found in a supergravity-motivated model recently, we propose a multi-field extension, in which two scalar fields are allowed to non-minimally couple to two vector…

General Relativity and Quantum Cosmology · Physics 2021-06-22 Tuan Q. Do , W. F. Kao

Local and global phase-space descriptions and averaging methods are used to find qualitative features of solutions for the FLRW and the Bianchi I metrics in the context of scalar field cosmologies with arbitrary potentials and arbitrary…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Genly Leon , Felipe Orlando Franz Silva

The nature of cosmological solutions for a homogeneous, anisotropic Universe given by a Bianchi type-I (BI) model in the presence of a Cosmological constant $\Lambda$ is investigated by taking into account dissipative process due to…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha , V. Rikhvitsky

We consider the dynamics of a Bianchi type I spacetime in the presence of dilaton and magnetic fields. The general solution of the Einstein-Maxwell dilaton field equations can be obtained in an exact parametric form. Depending on the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 T. Harko , M. K. Mak

The dynamics of the tilted axisymmetric Bianchi IX cosmological models are explored allowing energy flux in the source fluid. The Einstein equations and the continuity equation are presented treating the equation of state $w$ and the tilt…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-30 Peter Sundell , Tomi Koivisto

It was shown recently that a very simple nonlocal de Sitter gravity model contains exact vacuum cosmological solution which mimics dark energy and dark matter in flat space. Some other interesting solutions have been also found. In this…

General Relativity and Quantum Cosmology · Physics 2023-07-04 Ivan Dimitrijevic

The dynamics of cosmological anisotropies is investigated for Bianchi type I universe filled by a relativistic matter represented by the reduced relativistic gas model (RRG), with equation of state interpolating between radiation and…

General Relativity and Quantum Cosmology · Physics 2019-08-20 Simpliciano Castardelli dos Reis , Ilya L. Shapiro

The study of a self-consistent system of interacting spinor and scalar fields within the scope of a Bianchi type I (BI) gravitational field in presence of a viscous fluid and $\Lambda$ term has been carried out. The system of equations…

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

We uncover the solution space of a five dimensional geometry which we deem it as the direct counterpart of the Bianchi Type V cosmological model. We kinematically reduce the scale factor matrix and then, with an appropriate scaling and…

General Relativity and Quantum Cosmology · Physics 2025-04-01 Homa Shababi , Theophanes Grammenos , Nikolaos Dimakis , Andronikos Paliathanasis , Theodosios Christodoulakis

We present general exact solutions for two classes of exponential potentials in scalar field models for quintessence. The coupling is minimal and we consider only dust and scalar field. To some extent, it is possible to reproduce…

Astrophysics · Physics 2008-11-26 C. Rubano , P. Scudellaro

We study the anisotropic Bianchi I loop quantum cosmology in 2+1 dimensions. Both the $\mubar$ and $\mubar'$ schemes are considered in the present paper and the following expected results are established: (i) the massless scalar field again…

General Relativity and Quantum Cosmology · Physics 2020-10-23 You Ding , Xiangdong Zhang

Some new exact solutions of Einstein's field equations in a spatially homogeneous and anisotropic Bianchi type-V space-time with minimally interaction of perfect fluid and dark energy components have been obtained. To prevail the…

General Physics · Physics 2011-10-06 Anirudh Pradhan , H. Amirhashchi

The behaviour of magnetic field in anisotropic Bianchi type I cosmological model for bulk viscous distribution is investigated. The distribution consists of an electrically neutral viscous fluid with an infinite electrical conductivity. It…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Anirudh Pradhan , Sanjay Kumar Singh

We consider the emergent universe scenario supported by a chiral cosmological model with two interacting dark sector fields: phantom and canonical. We investigate the general properties of the evolution of the kinetic and potential energies…

General Relativity and Quantum Cosmology · Physics 2013-12-09 A. Beesham , S. V. Chervon , S. D. Maharaj , A. S. Kubasov

The cosmological singularities of the Bianchi I universe are analyzed in the setting of loop geometry underlying the loop quantum cosmology. We solve the Hamiltonian constraint of the theory and find the Lie algebra of elementary…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Piotr Dzierzak , Wlodzimierz Piechocki

We present new classes of exact solutions for an Emergent Universe supported by phantom and canonical scalar fields in the framework of a two-component chiral cosmological model. We outline in detail the method of deriving exact solutions,…

General Relativity and Quantum Cosmology · Physics 2013-12-06 A. Beesham , S. V. Chervon , S. D. Maharaj , A. S. Kubasov
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