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Related papers: Dynamics of Potentials in Bianchi Type Scalar-Tens…

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Bouncing non-singular isotropic cosmological solutions are investigated in a simple model of scalar-tensor gravity. New families of such solutions are found and their properties are presented and analyzed using an effective potential as the…

General Relativity and Quantum Cosmology · Physics 2022-01-28 D. Polarski , A. A. Starobinsky , Y. Verbin

We study scale dependence of the cosmic microwave background (CMB) power spectrum in a class of small, single-field models of inflation which lead to a high value of the tensor to scalar ratio. The inflaton potentials that we consider are…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-28 Ira Wolfson , Ram Brustein

A new class of exact solutions of Einstein's field equations with perfect fluid for an LRS Bianchi type-I spacetime is obtained by using a time dependent deceleration parameter. We have obtained a general solution of the field equations…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anirudh Pradhan , S. Otarod

In this paper, a spatially homogeneous and anisotropic Bianchi type V model filled with an imperfect fluid with bulk viscosity and particle creation, is investigated within the framework of General Relativity. Particle creation and bulk…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Mohd. Zeyauddin , Bijan Saha

The conditions under which cosmologies driven by time varying cosmological terms can be described by a scalar field coupled to a perfect fluid are discussed. An algorithm to reconstruct potentials dynamically and thermodynamically analogue…

Astrophysics · Physics 2009-11-07 J. M. F. Maia , J. A. S. Lima

We present a new approach of the reconstruction method based on the use of the cosmic parameters instead of a time law for the scale factor. This allows the derivation and analysis of a set of new non-trivial cosmological solutions for…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Sante Carloni , Rituparno Goswami , Peter K. S. Dunsby

The anisotropic Bianchi type I in multi-scalar field cosmology is studied with a particular potential of the form $\rm V= V_0 e^{-\left[\lambda_1 \phi_1 + \cdots + \lambda_n \phi_n \right]}\,,$ which emerges as a condition between the time…

General Relativity and Quantum Cosmology · Physics 2019-04-02 j. Socorro , Omar E. Núñez , Rafael Hernández-Jiménez

We discuss the phenomenological model in which the potential energy of the quintessence field depends linearly on the energy density of the spatial curvature. We find that the pressure of the scalar field takes a different form when the…

High Energy Physics - Theory · Physics 2014-11-18 Yungui Gong , Anzhong Wang , Yuan-Zhong Zhang

In this paper we investigate a Bianchi type I transitioning Universe in Brans-Dicke theory. To get an explicit solution of the field equations, we assume scalar field as $\phi = \phi_{0}\left[t^{\alpha}exp(\beta t)\right]^{\delta}$ with…

General Relativity and Quantum Cosmology · Physics 2020-11-19 Anil Kumar Yadav , A. M. Alshehri , Nafis Ahmad , G. K. Goswami , Mukesh Kumar

This article describes the theory of cosmological perturbations around a homogeneous and anisotropic universe of the Bianchi I type. Starting from a general parameterisation of the perturbed spacetime a la Bardeen, a complete set of gauge…

Astrophysics · Physics 2008-11-26 Thiago S. Pereira , Cyril Pitrou , Jean-Philippe Uzan

We explore non-canonical scalar field model in the background of non-flat $D$-dimensional fractal Universe with cosmological constant $\Lambda$ on the condition that the matter and scalar field are separately conserved. The potential $V$,…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Ujjal Debnath , Kazuharu Bamba

We discuss a spatially homogeneous and anisotropic Bianchi type-I space-time with two fluids as the content of the Universe: matter and holographic dark energy in the framework of general relativity. To get the exact solutions of Einstein's…

General Relativity and Quantum Cosmology · Physics 2023-02-03 M. Koussour , M. Bennai

A class of positive curvature spatially homogeneous but anisotropic cosmological models within an Einstein-aether gravitational framework are investigated. The matter source is assumed to be a scalar field which is coupled to the expansion…

General Relativity and Quantum Cosmology · Physics 2019-03-27 R. J. van den Hoogen , A. A. Coley , B. Alhulaimi , S. Mohandas , E. Knighton , S. O'Neil

The Hyperextended Scalar Tensor theory with a potential is defined by three free functions: the gravitational function, the Brans-Dicke coupling function and the potential. Starting from the expression of the 3-volume and the potential as…

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

In the context of the Loop Quantum Cosmology we have analysed the holonomy correction to the classical evolution of the simplified Bianchi I model in the presence of vector fields. For the Universe dominated by a massive vector field or by…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Michal Artymowski , Zygmunt Lalak

This paper is devoted to study Bianchi type I cosmological model in Brans-Dicke theory with self-interacting potential by using perfect, anisotropic and magnetized anisotropic fluids. We assume that the expansion scalar is proportional to…

General Relativity and Quantum Cosmology · Physics 2015-06-04 M. Sharif , Saira Waheed

We study the dynamics of the field equations in a four-dimensional isotropic and homogeneous spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker geometry in the context of Einstein-Gauss-Bonnet theory with a matter source and a…

General Relativity and Quantum Cosmology · Physics 2023-08-02 Alfredo D. Millano , Genly Leon , Andronikos Paliathanasis

Recent many physicists suggest that the dark energy in the universe might result from the Born-Infeld(B-I) type scalar field of string theory. The universe of B-I type scalar field with potential can undergo a phase of accelerating…

High Energy Physics - Theory · Physics 2009-11-10 H. Q. Lu

In this work, we study tracker phantom dark energy models with a general parameterization of the scalar potentials. Our analysis also considers the scenario of having both phantom field and the cosmological constant as the dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-18 Francisco X. Linares Cedeño , Nandan Roy , L. Arturo Ureña-López

This paper investigates the possible cosmological implications of the presence of an antisymmetric tensor field related to a lack of commutatitivity of spacetime coordinates at the Planck era. For this purpose, such a field is promoted to a…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Elisabetta Di Grezia , Giampiero Esposito , Agostino Funel , Gianpiero Mangano , Gennaro Miele