Observational tests of non-adiabatic Chaplygin gas
نویسندگان
چکیده
منابع مشابه
Chaplygin gas with non-adiabatic pressure perturbations
Perturbations in a Chaplygin gas, characterized by an equation of state p = −A/ρ, may acquire non-adiabatic contributions if spatial variations of the parameter A are admitted. This feature is shown to be related to a specific internal structure of the Chaplygin gas. We investigate how perturbations of this type modify the adiabatic sound speed and influence the time dependence of the gravitati...
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Perturbations in a Chaplygin gas, characterized by an equation of state p = −A/ρ, may acquire non-adiabatic contributions if spatial variations of the parameter A are admitted. This feature is shown to be related to a specific internal structure of the Chaplygin gas. We investigate how perturbations of this type modify the adiabatic sound speed. A reduction of the effective sound speed compared...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2014
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2014/10/060