Viscous generalized Chaplygin gas as a unified dark fluid: including perturbation of bulk viscosity
نویسندگان
چکیده
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 −0.0000105−0.0000138−0.0000138 in 1, 2, 3σ regions, respectively, via theMarkovChainMonteCarlomethod. The result shows that when considering perturbations of the bulk viscosity, the current cosmic observations favor a smaller bulk viscosity coefficient.
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