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Related papers: Bimetric MOND as a framework for variable-$G$ theo…

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We study the background cosmology of the ghost-free, bimetric theory of gravity. We perform an extensive statistical analysis of the model using both frequentist and Bayesian frameworks and employ the constraints on the expansion history of…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-22 Yashar Akrami , Tomi S. Koivisto , Marit Sandstad

We describe scalar-bimetric theories where the dynamics of the Universe are governed by two separate metrics, each with an Einstein-Hilbert term. In this setting, the baryonic and dark matter components of the Universe couple to metrics…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Philippe Brax , Patrick Valageas

I review various ideas on MOND cosmology and structure formation beginning with non-relativistic models in analogy with Newtonian cosmology. I discuss relativistic MOND cosmology in the context of Bekenstein's theory and propose an…

Astrophysics · Physics 2009-11-11 R. H. Sanders

The competition between CDM and MOND to account for the `missing mass' phenomena is asymmetric. MOND has clearly demonstrated that a characteristic acceleration $a_0$ underlies the data and understanding what gives rise to $a_0$ is an…

Astrophysics · Physics 2007-05-23 James Binney

The discrepancy between two recently reported experimental values of the gravitational constant G was analysed within a differential version of MOND theory. In contrast to the most commonly accepted interpretation of MOND theory, it is…

General Relativity and Quantum Cosmology · Physics 2016-04-14 Norbert Klein

An important and useful relation is known to hold in two specific MOND theories. It pertains to low-acceleration, isolated systems of pointlike masses, m_p, at positions r_p, subject to gravitational forces F_p. It reads sum_p…

General Relativity and Quantum Cosmology · Physics 2014-01-17 Mordehai Milgrom

In braneworld models a variable vacuum energy may appear if the size of the extra dimension changes during the evolution of the universe. In this scenario the acceleration of the universe is related not only to the variation of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Ponce de Leon

Dark matter is hypothetical matter believed to address the missing mass problem in galaxies. However, alternative theories, such as Modified Newtonian Dynamics (MOND), have been notably successful in explaining the missing mass problem in…

Astrophysics of Galaxies · Physics 2024-10-24 M. A. Syaifudin , M. I. Arifyanto , H. R. T. Wulandari , F. A. M. Mulki

Modified Newtonian dynamics (MOND) and similar proposals can (at least partially) explain the excess rotation of galaxies or the equivalent mass-discrepancy acceleration, without (or by reducing) the requirement of dark matter halos. This…

General Relativity and Quantum Cosmology · Physics 2024-10-10 Robert Monjo

Astronomical observations reveal a major deficiency in our understanding of physics $-$ the detectable mass is insufficient to explain the observed motions in a huge variety of systems given our current understanding of gravity, Einstein's…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-07 Indranil Banik , Hongsheng Zhao

MOND-- modified Newtonian dynamics-- may be viewed as an algorithm for calculating the distribution of force in an astronomical object from the observed distribution of baryonic matter. The fact that it works for galaxies is quite…

Astrophysics · Physics 2008-06-17 R. H. Sanders

It is surprising that we hardly know only 5% of the universe. Rest of the universe is made up of 70% of dark-energy and 25% of dark-matter. Dark-energy is responsible for acceleration of the expanding universe; whereas dark-matter is said…

General Physics · Physics 2011-04-06 R. C. Gupta , Anirudh Pradhan

Bimetric gravity is a ghost-free and observationally viable extension of general relativity, exhibiting both a massless and a massive graviton. The observed abundances of light elements can be used to constrain the expansion history of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-04 Marcus Högås , Edvard Mörtsell

Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including…

General Relativity and Quantum Cosmology · Physics 2018-09-17 M. E. S. Alves , F. C. Carvalho , J. C. N. de Araujo , M. Penna-Lima , S. D. P. Vitenti

Modified Newtonian dynamics (MOND), which postulates a breakdown of Newton's laws of gravity/dynamics below some critical acceleration threshold, can explain many otherwise puzzling observational phenomena on galactic scales. MOND competes…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-15 David Vokrouhlický , David Nesvorný , Scott Tremaine

We consider modifications of General Relativity obtained by adding the logarithm of some curvature invariants to the Einstein-Hilbert action. These non-linear actions can explain the late-time acceleration of the universe giving an…

Astrophysics · Physics 2007-05-23 I. Navarro , K. Van Acoleyen

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

In modelling galaxy structure formation, neither Cold Dark Matter (CDM) nor canonical Modified Newtonian Dynamics (MOND) (Milgrom [1]) can easily accommodate the appearance of massive galaxies at early times [2]. As a baseline We propose a…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-26 James C. C. Wong , Ray J. Rivers

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

Modified Newtonian dynamics (MOND) is an empirical theory originally proposed to explain the rotation curves of spiral galaxies by modifying the gravitational acceleration, rather than by invoking dark matter. Here,we set constraints on…

Astrophysics of Galaxies · Physics 2015-10-28 Fabio Iocco , Miguel Pato , Gianfranco Bertone