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arXiv · 1306.2168

Bianchi type V bulk viscous cosmological models with particle creation in General Relativity

Mohd. Zeyauddin·Bijan Saha
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Abstract

In this paper, a spatially homogeneous and anisotropic Bianchi type V model filled with an imperfect fluid with bulk viscosity and particle creation, is investigated within the framework of General Relativity. Particle creation and bulk viscosity have been considered as separate irreversible processes. The energy- momentum tensor is modified to accommodate the viscous pressure and creation pressure which is associated with creation of matter out of gravitational field. Exact solutions of the field equations are obtained by applying a special law of variation of Hubble parameter. Using this assumption, we obtain two types of cosmological models. We find a singularity in the first model whereas second model is non-singular. Further we separately study the bulk viscosity and particle creation in each model considering four different cases. The bulk viscosity coefficient $\zeta$ is obtained for Truncated, Full Causal and Eckart theories in all cases. All physical parameters are calculated and thoroughly discussed in both models.

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Mohd. Zeyauddin, Bijan Saha. 2013-06-10. Bianchi type V bulk viscous cosmological models with particle creation in General Relativity. https://doi.org/10.1140/epjp/i2014-14177-0

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