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Related papers: Moffat's Modified Gravity tested on X-COP galaxy c…

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Modified gravity theories such as Modified Newtonian Dynamics (MOND) and Scalar-Tensor-Vector Gravity (STVG) have been proposed as alternatives to dark matter, but decisive tests have been hindered by degeneracies between baryonic structure…

Astrophysics of Galaxies · Physics 2026-05-12 Zheng-long Wang , Yue-Lin Sming Tsai , Lan Zhang , Yin Wu , Haining Li , Xiang-Xiang Xue , Hongsheng Zhao , Yi-Zhong Fan

A modified gravitational theory explains early universe and late time cosmology, galaxy and galaxy cluster dynamics. The modified gravity (MOG) theory extends general relativity (GR) by three extra degrees of freedom: a scalar field $G$,…

General Relativity and Quantum Cosmology · Physics 2020-10-30 J. W. Moffat

The equation of motion in the generally covariant modified gravity (MOG) theory leads, for weak gravitational fields and non-relativistic motion, to a modification of Newton's gravitational acceleration law. In addition to the metric…

General Relativity and Quantum Cosmology · Physics 2019-05-24 M. A. Green , J. W. Moffat

We apply our scalar-tensor-vector (STVG) modified gravity theory (MOG) to calculate the infall velocities of the two clusters constituting the Bullet Cluster 1E0657-06. In the absence of an applicable two-body solution to the MOG field…

General Relativity and Quantum Cosmology · Physics 2010-05-18 J. W. Moffat , V. T. Toth

The modified gravity (MOG) theory is applied to the gravitational wave binary merger GW190814 to demonstrate that the modified Tolman-Oppenheimer-Volkoff equation for a neutron star can produce a mass $M=2.6 -2.7 M_\odot$, allowing for the…

General Relativity and Quantum Cosmology · Physics 2020-08-17 J. W. Moffat

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

Modified Gravity (MOG) and Non-Local Gravity (NLG) are two alternative theories to General Relativity. They are able to explain the rotation curves of spiral galaxies and clusters of galaxies without including dark matter (Moffat & Rahvar…

Astrophysics of Galaxies · Physics 2017-11-09 M. H. Zhoolideh Haghighi , S. Rahvar

MOG is a fully relativistic modified theory of gravity based on an action principle. The MOG field equations are exactly solvable numerically in two important cases. In the spherically symmetric, static case of a gravitating mass, the…

General Relativity and Quantum Cosmology · Physics 2010-11-25 J. W. Moffat , V. T. Toth

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

The polarized images of a synchrotron emitting ring are studied in the spacetime of a rotating black hole in the Scalar-Tensor-Vector-Gravity (STVG) theory. The black hole owns an additional dimensionless MOG parameter described its…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Xin Qin , Songbai Chen , Zelin Zhang , Jiliang Jing

A simple model for the dynamics of the Magellanic Stream (MS), in the framework of modified gravity models is investigated. We assume that the galaxy is made up of baryonic matter out of context of dark matter scenario. The model we used…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Hosein Haghi , Sohrab Rahvar

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

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

The Lambda-CDM model is the best fit to cosmological data, and to the observed galactic rotation curves. However, in the absence of a direct detection of dark matter one should explore theories such as MOND, and perhaps also modified…

Astrophysics of Galaxies · Physics 2013-12-03 Priti Mishra , Tejinder P. Singh

The Modified Gravity Model (MOG) has been proposed as a solution to the dark matter problem, but it does not meet the gauge invariant condition. The aim of this work is to propose a gauge-invariant theory, which suggests that symmetry can…

General Relativity and Quantum Cosmology · Physics 2023-11-02 Shahin Rouhani , Sohrab Rahvar

Astrophysical data analysis of the weak-field predictions support the claim that modified gravity (MOG) theories provide a self-consistent, scale-invariant, universal description of galaxy rotation curves, without the need of non-baryonic…

Astrophysics of Galaxies · Physics 2009-08-09 J. R. Brownstein

A conformal coupling of the metric in the Jordan frame to the energy-momentum tensor, screens the scalar field gravitational coupling strength $G$ in modified gravity (MOG). The scalar field acquires a mass which depends on the local matter…

General Relativity and Quantum Cosmology · Physics 2014-10-14 J. W. Moffat

Our modified gravity theory (MOG) is a gravitational theory without exotic dark matter, based on an action principle. MOG has been used successfully to model astrophysical phenomena such as galaxy rotation curves, galaxy cluster masses, and…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 J. W. Moffat , V. T. Toth

Scalar-Tensor-Vector Gravity (STVG) is a theory that does not require dark components to describe astrophysical data. We aim at constraining the free parameters of STVG based on recent observations of the jet in M87. We derive the equations…

High Energy Astrophysical Phenomena · Physics 2017-10-31 Federico G. Lopez Armengol , Gustavo E. Romero

The equation of motion in the generally covariant modified gravity (MOG) theory leads for weak gravitational fields and the non-relativistic limit to a modification of the Newtonian gravitational acceleration law, expressed in terms of two…

Astrophysics of Galaxies · Physics 2016-10-31 J. W. Moffat