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arXiv · gr-qc/0703108

Asymptotically Shear-free and Twist-free Null Geodesic Congruences

Carlos Kozameh·Ezra T. Newman
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Abstract

We show that, though they are rare, there are asymptotically flat space-times that possess null geodesic congruences that are both asymptotically shear- free and twist-free (surface forming). In particular, we display the class of space-times that possess this property and demonstrate how these congruences can be found. A special case within this class are the Robinson- Trautman space-times. In addition, we show that in each case the congruence is isolated in the sense that there are no other neighboring congruences with this dual property.

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Carlos Kozameh, Ezra T. Newman. 2007-03-21. Asymptotically Shear-free and Twist-free Null Geodesic Congruences. https://doi.org/10.1088/0264-9381%2F24%2F11%2F019

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