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Related papers: Exact cosmological solutions for MOG

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Symmetry plays a crucial role in theoretical physics, especially Noether symmetry, which is a powerful approach for identifying the models at the fundamental level. The exact solution is provided within the point-like Lagrangian framework.…

General Relativity and Quantum Cosmology · Physics 2025-10-21 M. Mahmoudzadeh Baghbani , K. Atazadeh , M. Mousavi

In this work, a cosmological model is considered having two scalar fields minimally coupled to gravity with a mixed kinetic term. The model is characterized by the coupling function and the potential function which are assumed to depend on…

General Relativity and Quantum Cosmology · Physics 2023-02-17 Santu Mondal , Roshni Bhaumik , Sourav Dutta , Subenoy Chakraborty

We find an exact solution of Scalar-Tensor-Vector Gravity field equations that represents a black hole embedded in an expanding universe. This is the first solution of the kind found in the theory. We analyze the properties of the apparent…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Daniela Pérez , Gustavo E. Romero

In this paper, we investigate the Noether symmetries of a generalized scalar-tensor, Brans-Dicke type cosmological model, in which we consider explicit scalar field dependent couplings to the Ricci scalar, and to the scalar field kinetic…

General Relativity and Quantum Cosmology · Physics 2016-02-03 J. A. Belinchón , T. Harko , M. K. Mak

We consider Noether symmetry approach to find out exact cosmological solutions in $f(T)$-gravity. Instead of taking into account phenomenological models, we apply the Noether symmetry to the $f(T)$ gravity. As a result, the presence of such…

General Physics · Physics 2012-05-29 K. Atazadeh , F. Darabi

This paper explores Noether and Noether gauge symmetries of anisotropic universe model in $f(R,T)$ gravity. We consider two particular models of this gravity and evaluate their symmetry generators as well as associated conserved quantities.…

General Physics · Physics 2017-05-24 M. Sharif , Iqra Nawazish

New exact vacuum solutions with various singularities in the plane-symmetric spacetime are shown, and they are applied to the analysis of inhomogeneous cosmological models and colliding gravitational waves. One of the singularities can be…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Kenji Tomita

This paper explores exact cosmological solutions of anisotropic universe model through Noether symmetry technique in energy-momentum squared gravity. This theory resolves the primordial singularity and provides viable cosmological…

General Relativity and Quantum Cosmology · Physics 2023-05-24 M. Sharif , M. Zeeshan Gul

As an alternative to dark matter models, MOdified Gravity (MOG) theory can compensate for dark matter by a covariant modification of Einstein gravity. The theory introduces two additional scalar fields and one vector field. The aim is to…

Astrophysics of Galaxies · Physics 2015-06-16 J. W. Moffat , S. Rahvar

We review the {\it Noether Symmetry Approach} as a geometric criterion to select theories of gravity. Specifically, we deal with Noether Symmetries to solve the field equations of given gravity theories. The method allows to find out exact…

General Relativity and Quantum Cosmology · Physics 2018-09-25 Konstantinos F. Dialektopoulos , Salvatore Capozziello

The field equations for Scalar-Tensor-Vector-Gravity (STVG) or modified gravity (MOG) have a static, spherically symmetric black hole solution determined by the mass $M$ with two horizons. The strength of the gravitational constant is…

General Relativity and Quantum Cosmology · Physics 2015-05-05 J. W. Moffat

We investigate the cosmological consequences of a scalar-vector-tensor theory of gravity known as MOG. In MOG, in addition to metric tensor, there are two scalar fields $G(x)$ and $\mu(x)$, and one vector field $\phi_{\alpha}(x)$. Using the…

General Relativity and Quantum Cosmology · Physics 2016-09-13 Sara Jamali , Mahmood Roshan

We derive the full set of field equations based on Hossenfelder's recent covariant formulation of the emergent gravity model, along with perturbative and exact solutions. The exact solution describes a static, spherically-symmetric…

General Relativity and Quantum Cosmology · Physics 2018-12-26 Yen-Kheng Lim , Qing-hai Wang

We discuss scalar-tensor cosmology with an extra $R^{-1}$ correction by the Noether Symmetry Approach. The existence of such a symmetry selects the forms of the coupling $\omega(\phi)$, of the potential $V(\phi)$ and allows to obtain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 H. Motavali , S. Capozziello , M. Rowshan Almeh Jog

We present a theory of modified gravity, inspired by the gauge theories, where the commutator algebra of covariant derivative gives us an added term with respect to the General Relativity, which represents the interaction of gravity with a…

General Relativity and Quantum Cosmology · Physics 2012-01-05 M. Hamani Daouda , Manuel E. Rodrigues , M. J. S. Houndjo

Adopting Noether point symmetries, we classify and integrate dynamical systems coming from Horndeski cosmologies. The method is particularly effective both to select the form of Horndeski models and to derive exact cosmological solutions.…

General Relativity and Quantum Cosmology · Physics 2018-07-04 Salvatore Capozziello , Konstantinos F. Dialektopoulos , Sergey V. Sushkov

This paper studies the cosmological equations for a scalar field Phi in the framework of a quantum gravity modified Einstein--Hilbert Lagrangian where G and Lambda are dynamical variables. It is possible to show that there exists a Noether…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alfio Bonanno , Giampiero Esposito , Claudio Rubano , Paolo Scudellaro

The form of the coupling of the scalar field with gravity and the potential have been found by applying Noether theorem to two dimensional minisuperspaces in induced gravity model. It has been observed that though the forms thus obtained…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. K. Sanyal , B. Modak

We explore the recently introduced modified Gauss-Bonnet gravity [1], $f(\mathcal{G},T)$ pragmatic with $\mathcal{G}$, the Gauss-Bonnet term, and ${T}$, the trace of the energy-momentum tensor. Noether symmetry approach has been used to…

General Physics · Physics 2017-01-31 M. Farasat Shamir , Mushtaq Ahmad

Scalar-tensor gravitational theories are important extensions of standard general relativity, which can explain both the initial inflationary evolution, as well as the late accelerating expansion of the Universe. In the present paper we…

General Relativity and Quantum Cosmology · Physics 2017-06-28 J. A. Belinchón , T. Harko , M. K. Mak