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Hawking radiation from spherically symmetrical gravitational collapse to an extremal R-N black hole for a charged scalar field

Hongbao Zhang·Zhoujian Cao·Chongshou Gao
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Abstract

Sijie Gao has recently investigated Hawking radiation from spherically symmetrical gravitational collapse to an extremal R-N black hole for a real scalar field. Especially he estimated the upper bound for the expected number of particles in any wave packet belonging to $\mathcal{H}_{out}$ spontaneously produced from the state $|0>_{in}$, which confirms the traditional belief that extremal black holes do not radiate particles. Making some modifications, we demonstrate that the analysis can go through for a charged scalar field.

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Hongbao Zhang, Zhoujian Cao, Chongshou Gao. 2003-08-20. Hawking radiation from spherically symmetrical gravitational collapse to an extremal R-N black hole for a charged scalar field. https://doi.org/10.1088/0253-6102%2F41%2F3%2F385

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