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Using clocks to determine the entropy of black holes and other space-time singularities

Akinbo Ojo
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Abstract

Space-time singularities, viz. Big bang, Big crunch and black holes have been shown to follow from the singularity theorems of General relativity. Whether the entropy at such infinite proper-time objects can be other than zero has also been a longstanding subject of research. Currently the property most commonly chosen to calculate their entropy is a multiple of the surface area of the event horizon and usually gives non-zero entropy values. Though popular, this choice still leaves some substantial questions unanswered hence the motivation for alternative methods for entropy derivation. Here, we use a different property, the proper-time at singularities based on the General relativity predicted behavior of clocks, to derive their entropy. We find, firstly within statistical and thermodynamic principles, secondly when this property is taken into account in the Bekenstein-Hawking formula and thirdly illustrating with a natural analogue, that the entropy of black holes and all other gravitational singularities cannot be other than zero as had been earlier classically speculated.

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Akinbo Ojo. 2005-03-31. Using clocks to determine the entropy of black holes and other space-time singularities. https://arxiv.org/abs/gr-qc/0502120

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