Tiberiu Harko, Francisco S. N. Lobo, M. K. Mak, Sergey V. Sushkov
We consider the density profile of pressureless dark matter in Eddington-inspired Born-Infeld (EiBI) gravity. The gravitational field equations are investigated for a spherically symmetric dark matter galactic halo, by adopting a phenomenological tangential velocity profile for test particles moving in stable circular orbits around the galactic center. The density profile and the general form of the metric tensor is obtained in an analytical form for both physical-$g$ and auxiliary-$q$ metrics, to a first order approximation. The dark matter density distribution is described by the Lane-Emden equation with polytropic index $n=1$, and is non-singular at the galactic center. The gravitational properties of the dark matter halos are also briefly discussed in the Newtonian approximation.
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http://arxiv.org/abs/1305.0820
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