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arXiv · 1110.6708

Black Holes in the Universe: Generalized Lemaitre-Tolman-Bondi Solutions

Changjun Gao·Xuelei Chen·You-Gen Shen·Valerio Faraoni
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Abstract

We present new exact solutions {which presumably describe} black holes in the background of a spatially flat, pressureless dark matter (DM)-, or dark matter plus dark energy (DM+DE)-, or quintom-dominated universe. These solutions generalize Lemaitre-Tolman-Bondi metrics. For a DM- or (DM+DE)-dominated universe, the area of the black hole apparent horizon (AH) decreases with the expansion of the universe while that of the cosmic AH increases. However, for a quintom-dominated universe, the black hole AH first shrinks and then expands, while the cosmic AH first expands and then shrinks. A (DM+DE)-dominated universe containing a black hole will evolve to the Schwarzschild-de Sitter solution with both AHs approaching constant size. In a quintom-dominated universe, the black hole and cosmic AHs will coincide at a certain time, after which the singularity becomes naked, violating Cosmic Censorship.

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Changjun Gao, Xuelei Chen, You-Gen Shen, Valerio Faraoni. 2011-10-31. Black Holes in the Universe: Generalized Lemaitre-Tolman-Bondi Solutions. https://doi.org/10.1103/physrevd.84.104047

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