WMAP and the generalized Chaplygin gas

  title={WMAP and the generalized Chaplygin gas},
  author={Luca Amendola and Fabio Finelli and Carlo Burigana and Daniel Carturan},
  journal={Journal of Cosmology and Astroparticle Physics},
We compare the WMAP temperature power spectrum and SNIa data to models with a generalized Chaplygin gas as dark energy. The generalized Chaplygin gas is a component with an exotic equation of state, pX = −A/ραX (a polytropic gas with negative constant and exponent). Our main result is that, restricting to a flat universe and to adiabatic pressure perturbations for the generalized Chaplygin gas, the constraints at 95% CL to the present equation of state wX = pX/ρX and to the parameter α are −1… 

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