Two Metrics unsuitable for Black Holes embedded in Expanding Universe
نویسنده
چکیده
How to describe a black hole embedded in an expanding universe is an important topic. Many models about this issue are suggested by assuming that the metric is a conformal transformation of the Schwarzschild metric or of the isotropic black hole metric. In the paper, it is shown that the two metrics are not suitable for describing a black hole embedded in an expanding universe because of the singularity at the event horizon. PACS: 04.70.Bw 04.70.-s 95.30.Sf
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