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Related papers: The phase space analysis of modified gravity (MOG)

200 papers

We examine the cosmological sector of a gauge theory of gravity based on the SO(4,2) conformal group of Minkowski space. We allow for conventional matter coupled to the spacetime metric as well as matter coupled to the field that gauges…

General Relativity and Quantum Cosmology · Physics 2017-05-02 Jack Gegenberg , Shohreh Rahmati , Sanjeev S. Seahra

We consider late-time cosmology in a (phantom) scalar-tensor theory with an exponential potential, as a dark energy model with equation of state parameter close to -1 (a bit above or below this value). Scalar (and also other kinds of)…

High Energy Physics - Theory · Physics 2009-09-17 Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov

Modified Gravity (MOG) has been used successfully to explain the rotation curves of galaxies, the motion of galaxy clusters, the Bullet Cluster, and cosmological observations without the use of dark matter or Einstein's cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 J. W. Moffat

Scalar Tensor Vector Gravity(STVG) is a fully covariant Lorentz invariant alternative theory of gravity also called as MOdified Gravity(MOG) which modifies General Relativity(GR) with dynamical massive vector field and scalar fields. In…

General Relativity and Quantum Cosmology · Physics 2022-04-13 Sreekanth Harikumar , Marek Biesiada

One way to account for the acceleration of the universe is to modify general relativity, rather than introducing dark energy. Typically, such modifications introduce new degrees of freedom. It is interesting to consider models with no new…

Astrophysics · Physics 2011-05-12 Sean M. Carroll , Ignacy Sawicki , Alessandra Silvestri , Mark Trodden

A scalar-tensor theory of gravity is considered wherein the gravitational coupling $G$ and the speed of light $c$ are admitted as space-time functions and combine to form the definition of the scalar field $\phi$. The varying $c$…

General Relativity and Quantum Cosmology · Physics 2023-04-05 Rodrigo R. Cuzinatto , Rajendra P. Gupta , Pedro J. Pompeia

This paper is dedicated to scrutinizing the cosmology in massive gravity. A matter field of the dark sector is coupled to an effective composite metric while a standard matter field couples to the dynamical metric in the usual way. For this…

General Relativity and Quantum Cosmology · Physics 2016-09-21 Lavinia Heisenberg , Alexandre Refregier

We analyze consequences of trying to replace dark matter and dark energy with models of stochastic spacetime. In particular, we analyze the model put forth by Ref. [1], in which it is claimed that ``post-quantum classical gravity" (PQCG), a…

General Relativity and Quantum Cosmology · Physics 2024-09-23 Mark P. Hertzberg , Abraham Loeb

Very recently, Verlinde considered a theory in which space is emergent through a holographic scenario, and proposed that gravity can be explained as an entropic force caused by changes in the information associated with the positions of…

General Relativity and Quantum Cosmology · Physics 2010-08-17 Hao Wei

In this work we present a few simple cosmological models under the modified theory of gravity in the particular form of $f(R,\mathcal{T})=R+2f(\mathcal{T})$, where $R$ is the Ricci Scalar and $\mathcal{T}$ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2021-06-14 B. Mishra , S. K. Tripathy , Saibal Ray

We consider a higher dimensional gravity theory with a negative kinetic energy scalar field and a cosmological constant. We find that the theory admits an exact cosmological solution for the scale factor of our universe. It has the feature…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. T. Hong , J. Lee , T. H. Lee , P. OH

Within the effective field theory approach to cosmic acceleration, the background expansion can be specified separately from the gravitational modifications. We explore the impact of modified gravity in a background different from a…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Guilherme Brando , Felipe T. Falciano , Eric V. Linder , Hermano E. S. Velten

We have explored a transitioning cosmic model, depicting late-time accelerated expansion in $f(R,T^{\phi})$ theory of gravity for an isotropic and homogeneous universe, where the trace of energy-momentum tensor $T^{\phi}$ is the function of…

General Relativity and Quantum Cosmology · Physics 2024-03-29 Bhojraj Singh Jayas , Vinod Kumar Bhardwaj

The main goal of the present work is to analyze the cosmological scenario of the induced gravity theory developed in previous works. Such a theory consists on a Yang-Mills theory in a four-dimensional Euclidian spacetime with $SO(m,n)$ such…

General Relativity and Quantum Cosmology · Physics 2017-08-24 F. T. Falciano , G. Sadovski , R. F. Sobreiro , A. A. Tomaz

Modified Gauss-Bonnet, i.e, $f(G)$ gravity is a possible explanation of dark energy. Late time cosmology for the $f(G)$ gravity non-minimally coupled with a free massless scalar field have been investigated in Ref. [32]. In this paper we…

High Energy Physics - Theory · Physics 2009-09-28 J Sadeghi , M R Setare , A Banijamali

The MOdified Gravity (MOG) theory of J. Moffat assumes a massive vector particle which causes a repulsive contribution to the tensor gravitation. For the galaxy cluster A1689 new data for the X-ray gas and the strong lensing properties are…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-28 Theodorus M. Nieuwenhuizen , Andrea Morandi , Marceau Limousin

We investigate the cosmological implications of a new class of modified gravity, where the field equations generically include higher-order derivatives of the matter fields, arising from the introduction of non-dynamical auxiliary fields in…

General Relativity and Quantum Cosmology · Physics 2016-07-01 Tiberiu Harko , Francisco S. N. Lobo , Emmanuel N. Saridakis

We have found some analytical cosmological solutions to MOdified Gravity (MOG). These solutions describe different evolutionary epochs of an isotropic and homogeneous universe. During each epoch, the evolution of cosmological perturbation…

General Relativity and Quantum Cosmology · Physics 2017-05-04 Fatimah Shojai , Samira Cheraghchi , Hamed Bouzari Nezhad

A relativistic modified gravity (MOG) theory leads to a self-consistent, stable gravity theory that can describe the solar system, galaxy and clusters of galaxies data and cosmology.

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. W. Moffat

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