A METHOD TO TEST THE EXISTENCE OF REGULAR BLACK HOLES

Illustration of a black hole. Image Credit & Copyright: Alain Riazuelo

The existence of the singularity is an intrinsic problem of the General Relativity (GR).

At the fundamentally level, the resolution of the problem of the singularity lies with the expectation that under situations where quantum effects become strong, the behavior of gravity could possibly greatly deviate from that predicted by the classical theory of GR.

Regular black hole solution are proposed with the same spacetime geometry outside the horizon as the traditional black hole, but bears no singularity inside. Whether or not black hole singularities should exist, they would be covered by the black hole horizon. The black hole horizon serves as an information curtain hindering outside observers from directly observing the interior structure of the black hole, and determining that whether or not the black hole singularity does really exist.

A method is needed to check the correctness of the new constructions of regular black holes. In a recent paper (Deng & Cleaver 2016) the authors suggest to use the Hawking radiation as a possible method to probe into the structure of black holes.

Mechanism of the Hawking radiation near the event horizon.

Hawking radiation is black-body radiation that is predicted to be released by black holes, due to quantum effects near the event horizon.

The authors study the Hawking radiation through fermion tunnelling from one type regular black hole. They assess that results contain modifications from that of the traditional black hole, which confirms the possibility of employing the Hawking radiation as a promising method to probe into the structure of black holes as far as these modifications are testable at astronomical observations.

Deng & Cleaver 2016 - Hawking Radiation from Regular Black Hole as a Possible Probe for Black Hole Interior Structure (arXiv)
Hawking radiation - (Wikipedia)

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