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Related papers: Anisotropic universe with anisotropic sources

200 papers

In recent years, there have been increasing challenges to the cosmological principle, based on new observations of e.g. supernovae and the cosmic bulk flow. As a result, the cosmological community is speaking their concern for the…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Robbert W. Scholtens , Marcello Seri , Holger Waalkens , Rien van de Weygaert

Following the recent recognition of a positive value for the vacuum energy density and the realization that a simple Kantowski-Sachs model might fit the classical tests of cosmology, we study the qualitative behavior of three anisotropic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Paulo Aguiar , Paulo Crawford

We present an effective Eulerian description, in the non-relativistic regime, of the growth of cosmological perturbations around a homogeneous but anisotropic Bianchi I spacetime background. We assume a small deviation from isotropy,…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-10 Juan P. Beltrán Almeida , Josué Motoa-Manzano , Jorge Noreña , Thiago S. Pereira , César A. Valenzuela-Toledo

In this work, we study the effect of a magnetic field on the growth of cosmological perturbations. We develop a mathematical consistent treatment in which a perfect fluid and a uniform magnetic field evolve together in a Bianchi I universe.…

General Relativity and Quantum Cosmology · Physics 2019-11-19 Federico Di Gioia , Giovanni Montani

We consider the dynamics of a viscous cosmological fluid in the generalized Randall-Sundrum model for an anisotropic, Bianchi type I brane. To describe the dissipative effects we use the Israel-Hiscock-Stewart full causal thermodynamic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Harko , M. K. Mak

We study the growth of perturbations in an expanding Bianchi type-I metric that evolves according to an energy density that includes dust and a cosmological constant. Assuming an epoch where the cosmological constant is subdominant, we find…

High Energy Physics - Theory · Physics 2010-02-03 E. Dimastrogiovanni , W. Fischler , S. Paban

The possible anisotropic nature in the early phases of the Universe is one of the interesting aspects of study in cosmology. We investigate the evolution of the Universe in terms of few cosmological parameters considering an anisotropic…

General Relativity and Quantum Cosmology · Physics 2023-04-03 Pranjal Sarmah , Avik De , Umananda Dev Goswami

Evolution of an anisotropic universe described by a Bianchi type I (BI) model in presence of nonlinear spinor field has been studied by us recently in a series of papers. On offer the Bianchi models, those are both inhomogeneous and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bijan Saha

Understanding the early evolution of the universe requires models that incorporate possible quantum and anisotropic effects in its dynamics. In this work, we analyze the dynamical evolution of locally rotationally symmetric anisotropic…

General Relativity and Quantum Cosmology · Physics 2025-10-13 G. Oliveira-Neto , Y. Soncco Apaza

We study anisotropic Bianchi-I cosmology, incorporating quantum gravitational corrections into the Einstein equation through the scale-dependent Newton coupling and cosmological term, as determined by the flow equation of the effective…

General Relativity and Quantum Cosmology · Physics 2025-12-03 Chiang-Mei Chen , Akihiro Ishibashi , Rituparna Mandal , Nobuyoshi Ohta

In this paper, we present a model of transitioning universe with minimal interaction between perfect fluid and anisotropic dark energy in Bianchi I space-time. The two sources are assumed to minimally interacted and therefore their energy…

General Relativity and Quantum Cosmology · Physics 2016-08-19 Anil Kumar Yadav

I study the dynamical effects due to the Brans-Dicke scalar $\phi$-field at the early stages of a supposedly anisotropic Universe expansion in the scalar-tensor cosmology of Jordan-Brans-Dicke. This is done considering the behaviour of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 H. N. Núñez-Yépez

There are evidences that the cosmic microwave background (CMB) large-angle anomalies imply a departure from statistical isotropy and hence from the standard cosmological model. We propose a LCDM model extension whose dark energy component…

Astrophysics · Physics 2008-11-26 Davi C. Rodrigues

The field equations of Brans-Dicke gravity coupled to a mass-varying vector field are derived. Anisotropic cosmological solutions with a locally rotationally symmetric Bianchi type I metric and time-dependent scalar and electric vector…

General Relativity and Quantum Cosmology · Physics 2014-02-05 Ozgur Akarsu , Tekin Dereli , Neslihan Oflaz

We investigate the evolution of anisotropies in Bianchi I spacetimes within the framework of the 4D Einstein-Gauss-Bonnet scalar field theory. The field equations are formulated using dimensionless variables, and the asymptotic dynamics are…

General Relativity and Quantum Cosmology · Physics 2026-01-06 Alex Giacomini , Chevara Hansraj , Genly Leon , Andronikos Paliathanasis

In this paper we investigate the past evolution of an anisotropic Bianchi I universe in $R+R^2$ gravity. Using the dynamical system approach we show that there exists a new two-parameters set of solutions that includes both an isotropic…

General Relativity and Quantum Cosmology · Physics 2018-05-09 Daniel Müller , Angelo Ricciardone , Alexei A. Starobinsky , Aleksey Toporensky

We investigate the cosmological reconstruction in anisotropic universe for both homogeneous and inhomogeneous content of the universe. Special attention is attached to three interesting cases: Bianchi type-I, Bianchi type-III and…

General Relativity and Quantum Cosmology · Physics 2012-11-29 M. E. Rodrigues , M. J. S. Houndjo , D. Saez-Gomez , F. Rahaman

In this paper we investigate the fate of the universe with an anisotropic background sourced by anisotropic matter. We see the behaviour of the Raychaudhuri Equation and investigate wheather a congrurence of time like geodesics focus to a…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Manabendra Sharma

In this paper, we investigate anisotropic cosmological solutions within the framework of Born-Infeld-f(R) gravity, a modification of general relativity that incorporates higher-order curvature invariants. Specifically, we focus on the…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Salih Kibaroğlu

Despite having the somewhat successful description of accelerated cosmology, the early evolution of the universe always challenges mankind. Our promising approach lies in a new class of symmetric teleparallel theory of gravity named $f(Q)$,…

General Relativity and Quantum Cosmology · Physics 2022-01-25 Avik De , Sanjay Mandal , J. T. Beh , Tee-How Loo , P. K. Sahoo