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Related papers: Exact cosmological solutions for MOG

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A non-diagonal spherically symmetric tetrad field, involving four unknown functions of radial coordinate $r$, is applied to the equations of motion of f(T) gravity theory. A special exact vacuum solution with one constant of integration is…

General Relativity and Quantum Cosmology · Physics 2015-02-19 G. G. L. Nashed

This paper determines the existence of Noether symmetry in non-minimally coupled $f(R,T)$ gravity admitting minimal coupling with scalar field models. We consider a generalized spacetime which corresponds to different anisotropic and…

General Relativity and Quantum Cosmology · Physics 2017-04-26 M. Sharif , Iqra Nawazish

In this article we present a new exact solution for scalar field with cosmological constant in cylindrical symmetry. Associated cosmological models is discussed. One of them describes a Cyclic universe.

General Relativity and Quantum Cosmology · Physics 2010-01-07 Davood Momeni , H. Miraghaei

We sketch the main features of the Noether Symmetry Approach, a method to reduce and solve dynamics of physical systems by selecting Noether symmetries, which correspond to conserved quantities. Specifically, we take into account the…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Francesco Bajardi , Salvatore Capozziello , Tiziana Di Salvo , Francesca Spinnato

Modified gravity (MOG) is a covariant, relativistic, alternative gravitational theory whose field equations are derived from an action that supplements the spacetime metric tensor with vector and scalar fields. Both gravitational (spin 2)…

General Relativity and Quantum Cosmology · Physics 2018-03-14 M. A. Green , J. W. Moffat , V. T. Toth

We study the gravitomagnetism in the Scalar-Vector-Tensor theory or Moffat's Modified theory of Gravity(MOG). We compute the gravitomagnetic field that a slow-moving mass distribution produces in its Newtonian regime. We report that the…

General Relativity and Quantum Cosmology · Physics 2019-10-14 Qasem Exirifard

The present work deals with a multi-field cosmological model in a spatially flat FLRW space-time geometry. The usual Brans-Dicke(BD) field and another scalar field are minimally coupled to gravity while they interact with each other through…

General Relativity and Quantum Cosmology · Physics 2024-07-10 Dipankar Laya , Sourav Dutta , Subenoy Chakraborty

The Noether Symmetry approach is applied to study an extended teleparallel $f(T,\phi)$ gravity that contains the torsion scalar $T$ and the scalar field $\phi$ in the context of an Friedmann-Lema\^{i}tre-Robertson-Walker space-time. We…

General Relativity and Quantum Cosmology · Physics 2023-07-19 L. K. Duchaniya , B. Mishra , Jackson Levi Said

We study the special class of the exact solutions in cosmological models based on the Generalized Scalar-Tensor Gravity with non-minimal coupling of a scalar field to the Ricci scalar and to the Gauss-Bonnet scalar in 4D Friedmann universe…

General Relativity and Quantum Cosmology · Physics 2019-07-17 Igor V. Fomin , Sergey V. Chervon

The standard model of elementary particle physics and the theory of general relativity can be extended by the introduction of a vacuum variable which is responsible for the near vanishing of the present cosmological constant (vacuum energy…

High Energy Physics - Theory · Physics 2014-11-20 F. R. Klinkhamer , G. E. Volovik

This work investigates alternative theories of gravity, the solutions to their field equations and the constraints that can be imposed upon them from observation and experiment. Specifically, we consider the cosmologies and spherically…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. Clifton

In the framework of the recently proposed models of massive gravity, defined with respect to a de Sitter reference metric, we obtain new homogeneous and isotropic solutions for arbitrary cosmological matter and arbitrary spatial curvature.…

High Energy Physics - Theory · Physics 2015-06-05 David Langlois , Atsushi Naruko

We obtain the action of Moffat's Modified Gravity, (MOG), a scalar-tensor-vector theory of gravitation, by generalizing the Horava-Witten mechanism to fourteen dimensions. We show that the resulting theory is anomaly-free. We propose an…

High Energy Physics - Theory · Physics 2018-01-09 Alireza Sepehri , Tooraj Ghaffary , Yaghoob Naimi

Solutions to the field equations of the Nonsymmetric Gravitational Theory with $g_[i0] = 0$ are obtained for the homogeneous, plane-symmetric, time-dependent case, both in vacuum and in the presence of a perfect fluid. Cosmological…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pierre Savaria

The present work deals with cosmological solutions in $f(R,T)$ gravity theory for perfect fluid with constant equation of state ($\omega$). For a viable cosmological solution $\omega$ is restricted to $\omega<\dfrac{1}{3}$. Also depending…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Akash Bose , Gopal Sardar , Subenoy Chakraborty

The modified theories of gravity, especially the f(R) theory, have attracted much attention in recent years. In this context, we explore static plane symmetric vacuum solutions using the metric approach of this theory. The field equations…

General Relativity and Quantum Cosmology · Physics 2010-06-21 M. Sharif , M. Farasat Shamir

In this paper, we present a complete Noether Symmetry analysis in the framework of scalar-tensor cosmology. Specifically, we consider a non-minimally coupled scalar field action embedded in the FLRW spacetime and provide a full set of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-09 A. Paliathanasis , M. Tsamparlis , S. Basilakos , S. Capozziello

We investigate static cylindrical solutions within an extended theory of modified gravity. By incorporating various coupling functions through a straightforward boost symmetry approach, we establish the equations of motion in a…

General Relativity and Quantum Cosmology · Physics 2024-07-31 Davood Momeni , Phongpichit Channuie , Mudhahir Al-Ajmi

We discuss the Noether Symmetry Approach in the framework of Gauss-Bonnet cosmology showing that the functional form of the $F(R, {\cal G})$ function, where $R$ is the Ricci scalar and ${\cal G}$ is the Gauss-Bonnet topological invariant,…

General Relativity and Quantum Cosmology · Physics 2014-11-13 Salvatore Capozziello , Mariafelicia De Laurentis , Sergei D. Odintsov

In this paper we investigate spherically symmetric vacuum solutions of $f(R)$ gravity in a higher dimensional spacetime. With this objective we construct a system of non-linear differential equations, whose solutions depend on the explicit…

General Relativity and Quantum Cosmology · Physics 2014-11-18 T. R. P. Caramês , E. R. Bezerra de Mello
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