Fitting rotation curve of galaxies by de Rham-Gabadadze-Tolley massive gravity

TL;DR

This paper explores how a specific massive gravity theory can explain galaxy rotation curves without dark matter by fitting observational data with a modified gravity model, constraining graviton properties.

Contribution

It demonstrates that the dRGT massive gravity model can successfully fit galaxy rotation curves and provides constraints on graviton mass and coupling parameters.

Findings

Galaxy rotation curves can be fitted with a single gravity parameter.

The graviton mass is constrained to the range 10^{-21} to 10^{-30} eV.

Strong constraints on Yukawa coupling from Milky Way data.

Abstract

We investigate effects of massive graviton on the rotation curves of the Milky Way, spiral galaxies and Low Surface Brightness~(LSB) galaxies. Using a simple de Rham, Gabadadze, and Tolley (dRGT) massive gravity model, we find static spherically symmetric metric and a modified Tolman-Oppenheimer-Volkoff (TOV) equation. The dRGT nonlinear graviton interactions generate density and pressures which behave like a dark energy that can mimic the gravitational effects of a dark matter halo. We found that rotation curves of most galaxies can be fitted well by a single constant-gravity parameter $\gamma \sim m_{g}^{2}C \sim 10^{-28}~{\rm m^{-1}}$ corresponding to the graviton mass in the range $m_g \sim 10^{-21}-10^{-30} {\rm eV}$ depending on the choice of the fiducial metric parameter $C\sim 1-10^{18}~\text{m}$. Fitting rotation curve of the Milky Way puts strong constraint on the Yukawa-type coupling of the massive graviton exchange as a result of the shell effects.