Recovering the fundamental plane of galaxies by f (R) gravity

Abstract

The fundamental plane (FP) of galaxies can be recovered in the framework of f (R) gravity avoiding the issues related to dark matter to fit the observations. In particular, the power-law version f (R) proportional to R-n, resulting from the existence of Noether symmetries for f (R), is sufficient to implement the approach. In fact, relations between the FP parameters and the corrected Newtonian potential, coming from Rn, can be found and justified from a physical point of view. Specifically, we analyze the velocity distribution of elliptical galaxies and obtain that r(c), the scale-length depending on the gravitational system properties, is proportional to re, the galaxy effective radius. This fact points out that the gravitational corrections induced by f (R) can lead photometry and dynamics of the system. Furthermore, the main byproduct of such an approach is that gravity could work in different ways depending on the scales of self-gravitating systems. (C) 2016 Elsevier B.V. All rights reserved.