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arXiv · 2106.06651

Thakurta metric does not describe a cosmological black hole

Tomohiro Harada·Hideki Maeda·Takuma Sato
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Abstract

Recently, the Thakurta metric has been adopted as a model of primordial black holes. We show that the spacetime described by this metric has neither black-hole event horizon nor black-hole trapping horizon and involves the violation of all the standard energy conditions as a solution of the Einstein equation. Therefore, this metric does not describe a cosmological black hole in the early universe. It is pointed out that a contradictory claim by the other group stems from an incorrect choice of sign.

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Tomohiro Harada, Hideki Maeda, Takuma Sato. 2021-06-12. Thakurta metric does not describe a cosmological black hole. https://doi.org/10.1016/j.physletb.2022.137332

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