Milgrom's Law and Λ's Shadow: How Massive Gravity Connects Galactic and Cosmic Dynamics
Abstract
Massive gravity provides a natural solution for the dark energy problem of cosmology and is also a candidate for resolving the dark matter problem. I demonstrate that, assuming reasonable scaling relations, massive gravity can provide for Milgrom's law of gravity (or "modified Newtonian dynamics") which is known to remove the need for particle dark matter from galactic dynamics. Milgrom's law comes with a characteristic acceleration, Milgrom's constant, which is observationally constrained to $a_0\approx1.1\times10^{10}$ m/s$^2$. In the derivation presented here, this constant arises naturally from the cosmologically required mass of gravitons like $a_0\propto c\sqrt{\Lambda}\propto c H_0\sqrt{3\Omega_{\Lambda}}$, with $\Lambda$, $H_0$, and $\Omega_{\Lambda}$ being the cosmological constant, the Hubble constant, and the third cosmological parameter, respectively. My derivation suggests that massive gravity could be the mechanism behind both, dark matter and dark energy.
 Publication:

Journal of Korean Astronomical Society
 Pub Date:
 June 2015
 DOI:
 10.5303/JKAS.2015.48.3.191
 arXiv:
 arXiv:1506.00730
 Bibcode:
 2015JKAS...48..191T
 Keywords:

 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Phenomenology
 EPrint:
 4 pages. To appear in JKAS (submitted: 2015 March 11