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On Spacetimes Admitting Shear-free, Irrotational, Geodesic Timelike Congruences

Alan A. Coley·Des J. Mc Manus
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Abstract

A comprehensive analysis of general relativistic spacetimes which admit a shear-free, irrotational and geodesic timelike congruence is presented. The equations governing the models for a general energy-momentum tensor are written down. Coordinates in which the metric of such spacetimes takes on a simplified form are established. The general subcases of `zero anisotropic stress', `zero heat flux vector' and `two component fluids' are investigated. In particular, perfect fluid Friedmann-Robertson-Walker models and spatially homogeneous models are discussed. Models with a variety of physically relevant energy-momentum tensors are considered. Anisotropic fluid models and viscous fluid models with heat conduction are examined. Also, models with a perfect fluid plus a magnetic field or with pure radiation, and models with two non-collinear perfect fluids (satisfying a variety of physical conditions) are investigated. In particular, models with a (single) perfect fluid which is tilting with respect to the shear-free, vorticity-free and acceleration-free timelike congruence are discussed.

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Alan A. Coley, Des J. Mc Manus. 1994-05-16. On Spacetimes Admitting Shear-free, Irrotational, Geodesic Timelike Congruences. https://doi.org/10.1088/0264-9381%2F11%2F5%2F013

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