Bulk Viscous Matter-dominated Universes: Asymptotic Properties

Understand

By means of a combined use of the type Ia supernovae and H(z) data tests, together with the study of the asymptotic properties in the equivalent phase space - through the use of the dynamical systems tools - we demonstrate that the bulk viscous matter-dominated scenario is not a good model to explain the accepted cosmological paradigm, at least, under the parametrization of bulk viscosity considered in this paper.

• The main objection against such scenarios is the absence of conventional radiation and matter-dominated critical points in the phase space of the model.
• This entails that radiation and matter dominance are not generic solutions of the cosmological equations, so that these stages can be implemented only by means of unique and very specific initial conditions, i.
• e., of very unstable particular solutions.