Isotropic Cosmological Singularities I. Polytropic Perfect Fluid Spacetimes
نویسنده
چکیده
We consider the conformal Einstein equations for 1 ≤ γ ≤ 2 poly-tropic perfect fluid cosmologies which admit an isotropic singularity. For 1 < γ ≤ 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 γ = 1 (dust) is obtained when Bianchi type symmetry is assumed.
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