φ2 as dark matter

Abstract

In this paper, we consider φ2 scalar field potential as a candidate to dark matter. If it is an ultralight boson particle, it condensates like a Bose-Einstein system at very early times and forms the basic structure of the Universe. Real scalar fields collapse in equilibrium configurations which oscillate in space-time (oscillatons).The cosmological behaviour of the field equations are solved using the dynamical system formalism. We use the current cosmological parameters as constraints for the present value of the scalar field and reproduce the cosmological predictions of the standard Λ cold dark matter model with this model. Therefore, scalar field dark matter seems to be a good alternative to cold dark matter nature. © 2009 RAS.