Cold Dark Matter and Neutralinos

The fact that most of the Universe is dark and composed of new, exotic components has been established over the years by means of various sets of observations, which recently have converged into a consistent picture where the Universe is about critical and dominated by an exotic form of matter and by an unexpected type of dark energy. In terms of the density parameter Ω, the current view can be summarized as follows: the total amount of matter/energy of the Universe is Ωtot ≃ 1 at the 10% level and this is composed of a matter component ΩM ≃ 0.3 and a vacuum– energy component ΩΛ ≃ 0.7 [1]. The existence of both dark exotic matter and dark energy asks for extension of the standard model of fundamental interactions, since no known particle or field can represent either of these components. In this paper, we will deal with the problem of explaining the observed amount of dark matter, which we can summarize as: 0.05 < ∼ ΩMh 2 < ∼ 0.3, and with the studies related to the searches for dark matter particles. For an updated review on these subjects, see Ref. [2].