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Internal symmetry in Bianchi type-I cosmologies

Luis P. Chimento
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Abstract

Using the one-parameter internal symmetry group in the Bianchi type-I spacetime for cosmological models with a perfect fluid, we show that a system of coordinates exists in the associated internal space where two scale factors become equal. We find the general solution for an anisotropic model containing a perfect fluid with constant baryotropic index and investigate the asymptotic regimes. We obtain exact solutions for a set of anisotropic fluids which includes an anisotropic stiff fluid.

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Luis P. Chimento. 2003-06-23. Internal symmetry in Bianchi type-I cosmologies. https://doi.org/10.1103/physrevd.68.023504

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