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arXiv · gr-qc/9408038

Characterisation of orthogonal perfect fluid cosmological spacetimes

Naresh Dadhich·L. K. Patel·K. S. Govinder·P. G. L. Leach
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Abstract

We consider the general orthogonal metric separable in space and time variables in comoving coordinates. We then characterise perfect fluid models admitted by such a metric. It turns out that the homogeneous models can only be either FLRW or Bianchi I while the inhomogeneous ones can only admit $G_2 $ (two mutually as well as hypersurface orthogonal spacelike Killing vectors) isometry. The latter can possess singularities of various kinds or none. The non-singular family is however unique and cylindrically symmetric.

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Naresh Dadhich, L. K. Patel, K. S. Govinder, P. G. L. Leach. 1994-08-31. Characterisation of orthogonal perfect fluid cosmological spacetimes. https://arxiv.org/abs/gr-qc/9408038

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