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arXiv · 2203.13295

Detectable universes inside regular black holes

Zacharias Roupas
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Abstract

While spacetime in the vicinity outside astrophysical black holes is believed to be well understood, the event horizon and the interior remain elusive. Here, we discover a degenerate infinite spectrum of novel general relativity solutions with the same mass-energy and entropy that describe a dark energy universe inside an astrophysical black hole. This regular cosmological black hole is stabilized by a finite tangential pressure applied on the dual cosmological-black hole event horizon, localized up to a quantum indeterminacy. We recover the Bekenstein-Hawking entropy formula from the classical fluid entropy, calculated at a Tolman temperature equal to the cosmological horizon temperature. We further calculate its gravitational quasi-normal modes. We find that cosmological black holes are detectable by gravitational-wave experiments operating within the $\mu{\rm Hz}-{\rm Hz}$ range, like LISA space-interferometer.

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Zacharias Roupas. 2022-03-24. Detectable universes inside regular black holes. https://doi.org/10.1140/epjc%2Fs10052-022-10202-6

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