منابع مشابه
Spherical top-hat collapse of a viscous unified dark fluid
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The Eulerian description of an incompressible viscous fluid of constant density and temperature is concerned with the fluid velocity u(x, t) and pressure p(x, t) recorded at fixed positions x ∈ R, n = 3 as functions of time t. The solutions of the incompressible, inviscid Euler equations can be thought of as geodesic paths on an infinite dimensional group of transformations ([1]). This is done ...
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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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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2008
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2008.01.068