【摘 要】
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Some locally rotationally symmetric Bianchi type-Ⅰ cosmological solutions for a cloud string with bulk viscosity are presented. In the first case, an equation
【机 构】
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Department of Physics, Anhui Normal University, Wuhu 241000
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Some locally rotationally symmetric Bianchi type-Ⅰ cosmological solutions for a cloud string with bulk viscosity are presented. In the first case, an equation of state p = kλ and the relation between metric potentials R = ASn are considered, and the solution represents shearing non-rotating model with the bulk viscosity ζ∝ p1/2, where p is the rest energy density of the cloud of strings with particles attached to them, λ is the tension density of the cloud of strings, ζ is the coeffcient of the bulk viscosity, R and S are only the functions of time t, while A and k are constant. In the second case, the constant coefficient of bulk viscosity is considered.
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