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Exact solutions for null fluid collapse

Viqar Husain
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Abstract

Exact non-static spherically symmetric solutions of the Einstein equations for a null fluid source with pressure $P$ and density $ρ$ related by $P = kρ^a$ are given. The $a=1$ metrics are asymptotically flat for $1/2<k\le 1$ and cosmological for $0<k<1/2$. The $k=1$ metric is the known charged Vaidya solution. In general the metrics have multiple apparent horizons. In the long time limit, the asymptotically flat metrics are hairy black hole solutions that `fall between' the Schwarzschild and Reissner-Nordstrom metrics.

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Viqar Husain. 1995-11-03. Exact solutions for null fluid collapse. https://doi.org/10.1103/physrevd.53.r1759

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