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Cosmological Effects of a Class of Fluid Dark Energy Models

Daniela Carturan·Fabio Finelli
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Abstract

We study the impact of a generalized Chaplygin gas as a candidate for dark energy on CMB anisotropies. The generalized Chaplygin gas is a fluid component with an exotic equation of state, $p = - A/ρ^α$ (a polytropic gas with negative constant and exponent). Such component interpolates in time between dust and a cosmological constant, with an intermediate behaviour as $p=αρ$. Perturbations of this fluid are stable on small scales, but behave in a very different way with respect to standard quintessence. Moreover, a generalized Chaplygin gas could also represent an archetypal example of a phenomenological unified models of dark energy and dark matter. The results presented here show how the CMB anisotropies induced by this class of models differ from a $Λ$CDM model.

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Daniela Carturan, Fabio Finelli. 2002-11-28. Cosmological Effects of a Class of Fluid Dark Energy Models. https://doi.org/10.1103/physrevd.68.103501

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