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Related papers: Testing MOND with Ultra-Compact Dwarf Galaxies

200 papers

We have obtained high-resolution spectra of 23 ultra-compact dwarf galaxies (UCDs) in the Fornax cluster with -10.4>M_V>-13.5 mag (10^6<M/M_*<10^8), using FLAMES/Giraffe at the VLT. This is the largest homogeneous data set of UCD internal…

Despite the success of dark-matter models, unresolved issues require exploring alternatives such as modified gravity theories. In this context, we examine the compatibility of the Hyperconical Modified Gravity (HMG) with galaxy rotation…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-24 Robert Monjo

We present a new test of modified Newtonian dynamics (MOND) on galactic scales, based on the escape speed in the solar neighbourhood. This test is independent from other empirical successes of MOND at reproducing the phenomenology of…

Astrophysics · Physics 2009-10-08 Benoit Famaey , Jean-Philippe Bruneton , HongSheng Zhao

Ultra-compact dwarf galaxies (UCDs) are stellar systems with masses of around 10^7 to 10^8 Msun and half mass radii of 10-100 pc. They have some properties in common with massive globular clusters, however dynamical mass estimates have…

Astrophysics · Physics 2009-11-13 Holger Baumgardt , Steffen Mieske

Ultra Compact Dwarf Galaxies (UCDs) and dwarf galaxy nuclei have many common properties, such as internal velocity dispersions and colour-magnitude trends, suggesting tidally stripped dwarf galaxies as a possible UCD origin. However, UCDs…

Astrophysics of Galaxies · Physics 2015-06-15 Joel Pfeffer , Holger Baumgardt

General analytic arguments lead us to expect that in the modified dynamics (MOND) self-gravitating disks are more stable than their like in Newtonian dynamics. We study this question numerically, using a particle-mesh code based on a…

Astrophysics · Physics 2014-10-13 Rafael Brada , Mordehai Milgrom

Dynamical mass estimates of ultra-compact dwarfs galaxies and massive globular clusters in the Fornax and Virgo clusters and around the giant elliptical Cen A have revealed some surprising results: 1) above about 10^6 M_sun the…

Astrophysics · Physics 2007-10-10 M. Hilker , S. Mieske , H. Baumgardt , J. Dabringhausen

A general account of MOND theory is given. I start with the basic tenets of MOND, which posit departure from standard dynamics in the limit of low acceleration -- below an acceleration constant a0 -- where dynamics become scale invariant. I…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-16 Mordehai Milgrom

A number of theories of gravity have been proposed as proxies for dark matter in the regime of galaxies and cosmology. The recent observations of gravitational waves (GW170817) from the merger of two neutron stars, followed by an…

General Relativity and Quantum Cosmology · Physics 2022-08-17 Constantinos Skordis , Tom Zlosnik

Gravitational lensing is most often used as a tool to investigate the distribution of (dark) matter in the universe, but, if the mass distribution is known a priori, it becomes, at least in principle, a powerful probe of gravity itself.…

Astrophysics · Physics 2009-11-06 Daniel J. Mortlock , Edwin L. Turner

In recent work we proposed a novel theory of dark matter (DM) superfluidity that matches the successes of the LambdaCDM model on cosmological scales while simultaneously reproducing MOdified Newtonian Dynamics (MOND) phenomenology on…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-01 Justin Khoury

The presence of dark matter, though well established by indirect evidence, is yet to be observed directly. Various dark matter detection experiments running for several years have yielded no positive results. In view of these negative…

General Relativity and Quantum Cosmology · Physics 2022-05-26 Louise Rebecca , Arun Kenath , C Sivaram

This paper continues previous work on a novel alternative model of gravity, based on the theory of fractional-dimension spaces applied to Newton's law of gravitation. In particular, our Newtonian Fractional-Dimension Gravity is now applied…

General Relativity and Quantum Cosmology · Physics 2021-02-15 Gabriele U. Varieschi

Modified Newtonian Dynamics (MOND) is a paradigm that can do away with dark matter at galaxy scales, but displays a residual missing mass discrepancy in galaxy clusters. Prompted by the updated JWST-based gravitational lens model of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Benoit Famaey

The modified newtonian dynamics (MOND) paradigm of Milgrom can boast of a number of successful predictions regarding galactic dynamics; these are made without the assumption that dark matter plays a significant role. MOND requires…

Astrophysics · Physics 2014-10-13 Jacob D. Bekenstein

We model the velocity dispersion of the ultra-diffuse galaxy NGC 1052-DF2 using Newtonian gravity and modified gravity (MOG). The velocity dispersion predicted by MOG is higher than the Newtonian gravity prediction, but it is fully…

General Relativity and Quantum Cosmology · Physics 2018-11-08 J. W. Moffat , V. T. Toth

We performed a large spectroscopic survey of compact, unresolved objects in the core of the Hydra I galaxy cluster (Abell 1060), with the aim of identifying ultra-compact dwarf galaxies (UCDs), and investigating the properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 I. Misgeld , S. Mieske , M. Hilker , T. Richtler , I. Y. Georgiev , Y. Schuberth

We highlight phenomenological aspects of Verlinde's recent proposal to account for the mass anomalies in galactic systems without dark matter -- in particular in their relation to MOND. Welcome addition to the MOND lore as it is, this…

Astrophysics of Galaxies · Physics 2017-01-18 Mordehai Milgrom , Robert H. Sanders

MOND predictions are compared with the mass discrepancy, Gamma (the dynamical-to-baryon mass ratio) deduced from the recently measured rotation curve, for the gas-rich, dwarf galaxy KK246, "the only galaxy observed in the local void". KK246…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-07 Mordehai Milgrom

A sample of 197 X-ray emitting clusters of galaxies is considered in the context of Milgrom's modified Newtonian dynamics (MOND). It is shown that the gas mass, extrapolated via an assumed $\beta$ model to a fixed radius of 3 Mpc, is…

Astrophysics · Physics 2009-10-30 R. H. Sanders