Galactic Dynamics in General Relativity: the Role of Gravitomagnetism [CL]

http://arxiv.org/abs/2112.08290


It is a well known fact that, in the absence of Dark Matter, the observation of the rotation curves of galaxies cannot be explained in terms of Newtonian gravity. Rotation curves become flat in the outer regions, in contrast to what is expected according to Keplerian motion. The gravitational field far from the galactic center is weak enough to use Newtonian gravity, however even in the weak-field approximation, there are general relativistic effects without a Newtonian counterpart, such as the gravitomagnetic effects originating from mass currents. Using the gravitoelectromagnetic approach to the solution of Einstein equations in the weak-field and slow-motion approximation, we discuss some simple arguments that suggest the surprising result that gravitomagnetic effects may have an important role in understanding galactic dynamics. In addition, treating matter as a fluid of dust, we study the impact of post-Newtonian effects on the fluid vorticity.

Read this paper on arXiv…

M. Ruggiero, A. Ortolan and C. Speake
Thu, 16 Dec 21
29/83

Comments: 7 pages, comments are welcome