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Apparent Horizons in Vacuum Robinson-Trautman Spacetimes

E. W. M. Chow·A. W. -C. Lun
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Abstract

Vacuum asymptotically flat Robinson-Trautman spacetimes are a well known class of spacetimes exhibiting outgoing gravitational radiation. In this paper we describe a method of locating the past apparent horizon in these spacetimes, and discuss the properties of the horizon. We show that the past apparent horizon is non-timelike, and that its surface area is a decreasing function of the retarded time. A numerical simulation of the apparent horizon is also discussed.

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E. W. M. Chow, A. W. -C. Lun. 1995-04-01. Apparent Horizons in Vacuum Robinson-Trautman Spacetimes. https://arxiv.org/abs/gr-qc/9503065

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