Related papers: Errors in equations for galaxy rotation speeds
Assessing the likelihood that the rotation curve of a galaxy matches predictions from galaxy formation simulations requires that the uncertainties in the circular speed as a function of radius derived from the observational data be…
We obtain a more accurate statistical estimation of the mass of double galaxies moving in circular orbits, including confidence intervals for different confidence levels.
We use the hydrodynamical galaxy formation simulations from the Illustris suite to study the origin and properties of galaxy velocity bias, i.e., the difference between the velocity distributions of galaxies and dark matter inside halos. We…
A new simple expression for the circular velocity of spiral galaxies is proposed and tested against HI Nearby Galaxy Survey (THINGS) data set. Its accuracy is compared with the one coming from MOND.
We explore the distribution of mass about the expected sites of galaxy formation in a high-resolution hydrodynamical simulation of a LCDM cosmology which includes cooling, star-formation and feedback. We show that the evolution of the…
In this work, we submit the explanation of spectra of the rotary curves of galaxies on the basis of a vector theory of gravitation without regard to the dark matter hypothesis. We study the approximation of rotary curves in case of existing…
Using tidal disruption of globular clusters by the galactic center, we put limits on the total mass ever enclosed into orbits of observed globular clusters. Under the assumption that the rate of mass loss from the Galaxy is steady, we then…
Luminous galaxies and their dark halos are likely to have triaxial shapes. The construction of distribution functions for triaxial systems is a hard problem, due to the existence of only one exact integral of motion, the energy $E$. Even…
The information contained in galactic rotation curves is examined under a minimal set of assumptions. If emission occurs from stable circular geodesic orbits of a static spherically symmetric field, with information propagated to us along…
The discrepancy between the visible mass in galaxies or galaxy clusters, and that inferred from their dynamics is well known. The prevailing solution to this problem is dark matter. Here we show that a different approach, one that conforms…
The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies have been studied using the Planetary Nebula Spectrograph. The galaxies' velocity dispersion profiles are found to decline with radius; dynamical…
We suggest a new explanation of flatness of galaxies rotation curves without invoking dark matter. For this purpose a new gravitational tensor field is introduced in addition to the metric tensor.
It has long been known that Newtonian dynamics applied to the visible matter in galaxies and clusters does not correctly describe the dynamics of those systems. While this is generally taken as evidence for dark matter it is in principle…
It has been proposed that the flat rotation curves observed at large radii in disk galaxies can be interpreted as an effect of General Relativity (GR) instead of the presence of dark matter (DM) halos in Newtonian gravity. In Ciotti (2022)…
Rotation curves of spiral galaxies are the major tool for determining the distribution of mass in spiral galaxies. They provide fundamental information for understanding the dynamics, evolution and formation of spiral galaxies. We describe…
The circular velocities of the inner region of disk galaxies are predicted by standard physics but velocities beyond the stellar disks are not consistent with Newtonian physics if the material there is in stable circular orbits. However,…
Rotation curves constrain a galaxy's underlying mass density profile, under the assumption that the observed rotation produces a centripetal force that exactly balances the inward force of gravity. However, most rotation curves are measured…
The mass and anisotropy of an elliptical galaxy can be simultaneously determined from velocity dispersion and line profile shape measurements. We describe the principles, techniques, and limitations of this approach, and the results…
Recently, it has been suggested that the phenomenology of flat rotation curves observed at large radii in the equatorial plane of disk galaxies can be explained as a manifestation of General Relativity instead of the effect of Dark Matter…
In this paper we develop a calculation code to account for the effects carried by fast rotation on the observed spectra of early-type stars. Stars are assumed to be in rigid rotation and the grid of plane-parallel model atmospheres used to…