EAS Publications Series
Volume 36, 2009Dark Energy and Dark Matter: Observations, Experiments and Theories
|Page(s)||17 - 24|
|Published online||30 May 2009|
E. Pécontal, T. Buchert, Ph. Di Stefano and Y. Copin (eds)
EAS Publications Series, 36 (2009) 17-24
Newtonian approach to the matter power spectrum of the generalized chaplygin gas
Universidade Federal do Espírito Santo, Departamento de Física, Av. Fernando Ferrari, 514 Campus de Goiabeiras, CEP 29075-910, Vitória, Espírito Santo, Brazil.
2 Present adress: Institut d'Astrophysique de Paris - IAP, Paris, France
3 Present adress: Laboratoire d'Annecy-le-Vieux de Physique Théorique - LAPTH, Annecy-le-Vieux, France
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 α.
© EAS, EDP Sciences, 2009