Related papers: Using distant globular clusters as a test for grav…
We report that the density profiles of globular cluster (GC) systems in a sample of 17 early-type galaxies (ETGs) show breaks at the radii where the gravitational acceleration exerted by the stars equals the galactic acceleration scale…
Globular clusters are an important test bed for Newtonian gravity in the weak-acceleration regime, which is vital to our understanding of the nature of the gravitational interaction. Recent claims have been made that the velocity dispersion…
New measurements of the velocity dispersion of the globular cluster omega Centauri allow to trace its gravitational potential down to an acceleration of 8e-9 cm/s/s. It is found that the dispersion profile remains flat well inside the tidal…
Over the past couple of years, a number of observational studies have confirmed the flattening of the radial velocity dispersion profiles for stars in various nearby globular clusters. As the projected radial coordinate is increased, a…
This chapter presents Modified Newtonian Dynamics (MOND), the proposal that, below a certain acceleration scale $a_0$, dynamics departs from the Newtonian expectation. In that context, the determining factor for the emergence of apparent…
In this work, we propose a modified Newton dynamics (MOND) model to study the rotation curves of galaxies. The model is described by an arctangent interpolating function and it fits the rotation curves of several galaxies without invoking…
Milgrom's modified Newtonian dynamics (MOND) can explain well the mass discrepancy problem in galaxy without invoking dark matter. The MOND theory predicts a universal constant acceleration scale in galaxy, below which the Newtonian…
Galactic systems, and the Universe at large, exhibit large dynamical anomalies: The observed matter in them falls very short of providing enough gravity to account for their dynamics. The mainstream response to this conundrum is to invoke…
Without observational or theoretical modifications, Newtonian and general relativity seem to be unable to explain gravitational behavior of large structure of the universe. The assumption of dark matter solves this problem without modifying…
We consider for the first time the implications on the modified gravity MOND model of galaxies, of the presence of dark baryons, under the form of cold molecular gas in galaxy discs. We show that MOND models of rotation curves are still…
We examine the implications of Modified Newtonian Dynamics (MOND) on the large scale structure in a Friedmann-Robertson-Walker universe. We employ a ``Jeans swindle'' to write a MOND-type relationship between the fluctuations in the density…
We consider the feasibility of testing Newtonian gravity at low accelerations using wide binary (WB) stars separated by $\ge 3$ kAU. These systems probe the accelerations at which galaxy rotation curves unexpectedly flatline, possibly due…
Certain types of globular clusters have the very important property that the predictions for their kinematics in the Newtonian and modified Newtonian dynamics (MOND) contexts are divergent. Here, we caution the recent claim that the stellar…
We quantify the differences between stellar accelerations in disk galaxies formed in a MONDian universe relative to galaxies with the identical baryonic matter distributions and a fitted cold dark matter halo. In a Milky Way-like galaxy the…
The dynamics of galaxies in an expanding universe is often determined for gravitational and dark matter in an Einstein-de Sitter universe, or alternatively by modifying the gravitational long-range attractions in the Newtonian dynamics…
Using deep photometric data from WFC@INT and [email protected] we measure the outer number density profiles of 19 stellar clusters located in the inner region of the Milky Way halo (within a Galactocentric distance range of 10-30 kpc) in order to…
Analyses of halo shapes for disc galaxies are said to give incongruous results. I point out that the modified dynamics (MOND) predicts for disc galaxies a distribution of fictitious dark matter that comprises two components: a pure disc and…
In view of the negative results from various dark matter detection experiments, we had earlier proposed an alternate theoretical framework through Modification of Newtonian Gravity (MONG). Here, the Poison's equation is modified by…
Conformal geometry is considered within a general relativistic framework. An invariant distant for proper time is defined and a parallel displacement is applied in the distorted space-time, modifying Einstein's equation appropriately. A…
Polar ring galaxies are ideal objects with which to study the three-dimensional shapes of galactic gravitational potentials since two rotation curves can be measured in two perpendicular planes. Observational studies have uncovered…