منابع مشابه
Spherical top-hat collapse of a viscous unified dark fluid
In this paper, we test the spherical collapse of a viscous unified dark fluid (VUDF) which has constant adiabatic sound speed and show the nonlinear collapse forVUDF, baryons, and dark matter, which are important in forming the large-scale structure of our Universe. By varying the values of the model parameters α and ζ0, we discuss their effects on the nonlinear collapse of the VUDF model, and ...
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In this paper, we continue our previous work of studying viscous generalized Chaplygin gas as a unified dark fluid but the bulk viscosity perturbations. By using the currently available cosmic observational data from SNLS3, BAO, HST, and recently released Planck, we obtain a constraint on the bulk viscosity coefficient: ζ0 = 0.0000138+0.00000614+0.0000145+0.0000212 −0.0000105−0.0000138−0.000013...
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Cosmological observations are normally fit under the assumption that the dark sector can be decomposed into dark matter and dark energy components. However, as long as the probes remain purely gravitational, there is no unique decomposition and observations can only constrain a single dark fluid; this is known as the dark degeneracy. We use observations to directly constrain this dark fluid in ...
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2015
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s10052-015-3371-3