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arXiv · 2304.04427

Temperatures of AdS$_2$ black holes and holography revisited

Wontae Kim·Mungon Nam
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Abstract

In a dilaton gravity model, we revisit the calculation of the temperature of an evaporating black hole that is initially formed by a shock wave, taking into account the quantum backreaction. Based on the holographic principle, along with the assumption of a boundary equation of motion, we show that the black hole energy is maintained for a while during the early stage of evaporation. Gradually, it decreases as time goes on and eventually vanishes. Thus, the Stefan-Boltzmann law tells us that the black hole temperature, defined by the emission rate of the black hole energy, starts from zero temperature and reaches a maximum value at a critical time, and finally vanishes. It is also shown that the maximum temperature of the evaporating black hole never exceeds the Hawking temperature of the eternal AdS$_{2}$ black hole. We discuss physical implications of the initial zero temperature of the evaporating black hole.

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Wontae Kim, Mungon Nam. 2023-04-10. Temperatures of AdS$_2$ black holes and holography revisited. https://doi.org/10.1142/s0217732324501219

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