Related papers: The distinguishing factor for gravity models: stel…
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…
A low mass-to-light ratio for the stellar component of spiral galaxies (M/L<1 in the I-band) is advocated by various dynamical arguments and by recent cosmological simulations of the formation of these systems. We discuss this possibility…
We present a simple technique to estimate mass-to-light (M/L) ratios of stellar populations based on two broadband photometry measurements, i.e. a color-M/L relation. We apply the color-M/L relation to galaxy rotation curves, using a large…
Several independent lines of evidence suggest that the stellar initial mass function (IMF) in early-type galaxies becomes increasingly `bottom-heavy' with increasing galaxy mass and/or velocity dispersion, sigma. Here we consider evidence…
Observations indicate that the disc population in galaxy clusters has undergone rapid evolution, transitioning from a dominance of blue spirals to red S0s over the past $\sim7$ Gyr. We build a simplified cluster evolutionary model in the…
Unlike Newtonian dynamics which is linear and obeys the strong equivalence principle, in any nonlinear gravitation such as Milgromian dynamics (MOND), the strong version of the equivalence principle is violated and the gravitational…
Intermediate-richness galaxy groups are an important test ground for MOND. First, they constitute a distinct type of galactic systems, with their own evolution histories and underlying physical processes; secondly, they probe…
We present gravitational lens models for 20 strong gravitational lens systems observed as part of the Sloan WFC Edge-on Late-type Lens Survey (SWELLS) project. Fifteen of the lenses are taken from paper I while five are newly discovered…
I present a comparison between published dynamical (ATLAS3D) and spectroscopic (Conroy & van Dokkum) constraints on the stellar initial mass function (IMF) in early-type galaxies, using the 34 galaxies in common between the two works. Both…
We analyze the stellar mass-to-light ratio (M/L) gradients in a large sample of local galaxies taken from the Sloan Digital Sky Survey, spanning a wide range of stellar masses and morphological types. As suggested by the well known…
This paper addresses the challenge of understanding the typical star formation histories of red sequence galaxies, using linestrength indices and mass-to-light ratios as complementary constraints on their stellar age distribution. We…
The tight correlation between galaxy bulges and their central black hole masses likely emerges in a phase of rapid collapse and starburst at high redshift, due to the balance of gravity on gas with the feedback force from starbursts and the…
We determine an absolute calibration of the initial mass function (IMF) of early-type galaxies, by studying a sample of 56 gravitational lenses identified by the SLACS Survey. Under the assumption of standard Navarro, Frenk & White dark…
We currently have two different hypotheses to solve the missing mass problem: dark matter (DM) and modified Newtonian dynamics (MOND). In this work, we use Bayesian inference applied to the Spitzer Photometry and Accurate Rotation Curves…
An extensive catalog of spatially-resolved galaxy rotation curves and multi-band optical light profiles for 1752 observed spiral galaxies is assembled to explore the drivers of diversity in galaxy structural parameters, rotation curve…
A better understanding of the formation of mass structures in the universe can be obtained by determining the amount and distribution of dark and luminous matter in spiral galaxies. To investigate such matters a sample of 12 galaxies, most…
The rotation curves of low surface brightness (LSB) galaxies suggest that they possess significantly higher mass-to-light (M/L) ratios than their high surface brightness counterparts, indicating that LSB galaxies may be dark matter…
We present dynamical scaling relations, combined with the stellar population properties, for a subsample of about 6000 nearby galaxies with the most reliable dynamical models extracted from the full MaNGA sample of 10K galaxies. We show…
Dwarf galaxies have long been recognised as important testing grounds for models of dark matter. For instance, it is here where the cusp-core problem is most apparent. In this work we select two dwarf galaxy samples: LITTLE THINGS and dwarf…
Observations of mergers of multi-compact object systems offer insights to the formation processes of massive stars in globular clusters. Simulations of stellar clusters, may be used to understand and interpret observations. Simulations…