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Isotropic cosmological singularities 1: Polytropic perfect fluid spacetimes

K. Anguige·K. P. Tod
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Abstract

We consider the conformal Einstein equations for polytropic perfect fluid cosmologies which admit an isotropic singularity. For the polytropic index gamma strictly greater than 1 and less than or equal to 2 it is shown that the Cauchy problem for these equations is well-posed, that is to say that solutions exist, are unique and depend smoothly on the data, with data consisting of simply the 3-metric of the singularity. The analogous result for gamma=1 (dust) is obtained when Bianchi type symmetry is assumed.

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K. Anguige, K. P. Tod. 1999-03-02. Isotropic cosmological singularities 1: Polytropic perfect fluid spacetimes. https://doi.org/10.1006/aphy.1999.5946

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