# Isotropic Cosmological Singularities: I. Polytropic Perfect Fluid Spacetimes

@article{Anguige1999IsotropicCS, title={Isotropic Cosmological Singularities: I. Polytropic Perfect Fluid Spacetimes}, author={Keith Anguige and K. Paul Tod}, journal={Annals of Physics}, year={1999}, volume={276}, pages={257-293} }

Abstract We consider the conformal Einstein equations for 1⩽ γ ⩽2 polytropic 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, 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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