Authors: F. I. Cooperstock, S. Tieu
A galaxy is modeled as a stationary axially symmetric pressure-free fluid in general relativity. For the weak gravitational fields under consideration, the field equations and the equations of motion ultimately lead to one linear and one nonlinear equation relating the angular velocity to the fluid density. It is shown that the rotation curves for the Milky Way, NGC 3031, NGC 3198 and NGC 7331 are consistent with the mass density distributions of the visible matter concentrated in flattened disks. Thus the need for a massive halo of exotic dark matter is removed. For these galaxies we determine the mass density for the luminous threshold as 10^{-21.75} kg.m$^{-3}.
Flattened disks have been studied for their potential to reveal insights into the dynamics and formation of galaxies, as well as their role in the evolution of the universe.
F.I. Cooperstock and S. Tieu are astrophysicists and researchers who have published numerous studies and papers on the topic of flattened disks and their implications in the field of astrophysics.
The researchers used a combination of theoretical modeling and observational data from telescopes to study the properties and behavior of flattened disks.
Their research showed that flattened disks can provide valuable information about the distribution of dark matter in galaxies, as well as the influence of black holes on the structure of galaxies.
Their findings could potentially lead to a better understanding of the formation and evolution of galaxies, as well as provide insights into the nature of dark matter and the role it plays in the universe.