Abstract
[-5]The applications of Newtonian dynamics in galactic scales have shown that the inverse square law is incompatible with the amount of visible mass in the form of stars and molecular clouds. This manifests as the rotational curves of galaxies being asymptotically flat instead of decaying with the distance to the center of the galaxy. In the context of Newtonian gravity, the standard explanation requires a huge amount of dark mass in the form of hypothetical particles that still remain undetected. A different theory was provided as a modification of Newtonian dynamics (MOND) at low accelerations . This MOND theory still has many supporters and it can easily explain some features of the rotation curves, such as the Tully–Fisher (TF) phenomenological relation between luminosity and velocity. In this paper, we revisit the third approach of a non-Newtonian force, that has resurfaced from time to time, in order to reconcile it with a finite apparent dark mass and the TF relation.
Highlights
The dark matter hypothesis was proposed by the astronomer Fritz Zwicky after careful analysis of the motions in the Coma Cluster of galaxies [1]
Dark matter received little attention until the 1970s thanks to the new observations by Rubin and collaborators [2] as well as Faber and Gallagher [3]. These authors showed, unmistakably, that the rotation curves of many galaxies exhibit a flat asymptotic behavior that cannot be accommodated with the standard form of Newtonian gravity force and Newtonian dynamics
If we consider a set of hypothetical galaxies with the same mass functions as the Milky Way and the same parameters except for a and f, which would be scaled with n2, n = 2, 3, . . ., we find that the plateau velocity of the rotation curves can be obtained by performing the integrations in Equation (27) at the distance 8n Kpc
Summary
The dark matter hypothesis was proposed by the astronomer Fritz Zwicky after careful analysis of the motions in the Coma Cluster of galaxies [1]. The chance of detecting them is very low and relies on several hypotheses about the intensity of this coupling with standard matter [7,8] This makes DM epistemologically not very different from the apparent or phantom matter that would arise from a non-Newtonian law of gravity at large distances. In this paper we reexamine several proposals for a non-Newtonian law of force and the fitting of the apparent extra dark matter in models of the Milky Way. A possible square-root dependence with total mass of the fundamental distance scale associated with this new force is discussed in the context of the TF relation. We comment on the expected anomalies that may arise on the scale of the Solar System as a consequence of the non-Newtonian terms
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
