Newtonian Approach to the Matter Power Spectrum of the Generalized Chaplygin Gas

Abstract

We model the cosmic medium as the mixture of a generalized Chaplygin gas and a pressureless matter component. Within a neo-Newtonian approach we compute the matter power spectrum. The 2dFGRS data are used to discriminate between unified models of the dark sector and different models, for which there is separate dark matter, in addition to that accounted for by the generalized Chaplygin gas. Leaving the corresponding density parameters free, we find that the unified models are strongly disfavored. On the other hand, using unified model priors, the observational data are also well described, in particular for small and large values of the generalized Chaplygin gas parameter $\alpha$.

Latex file, 5 pages, 11 figures in eps format. For the proceedings of the conference Dark Energy and Dark Matter, 7-11 july 2008, Lyon, France

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Cited by in corpus (1)

• Observational constraints on a unified dark matter and dark energy model based on generalized Chaplygin gas