Eur. Phys. J. C (2012) 72: 1987
https://doi.org/10.1140/epjc/s10052-012-1987-0

Regular Article - Theoretical Physics

Spectroscopy of a Reissner–Nordström black hole via an action variable

¹ Department of Physics, Institute of Theoretical Physics, Beijing Normal University, Beijing, 100875, China
² Department of Physics and Engineering Technology, Sichuan University of Arts and Science, Dazhou, 635000, Sichuan, China

^* e-mail: wbliu@bnu.edu.cn

Received: 23 February 2012
Revised: 27 March 2012
Published online: 24 April 2012

Abstract

With the help of the Bohr–Sommerfeld quantization rule, the area spectrum of a charged, spherically symmetric spacetime is obtained by studying an adiabatic invariant action variable. The period of the Einstein–Maxwell system, which is related to the surface gravity of a given spacetime, is determined by Kruskal-like coordinates. It is shown that the area spectrum of the Reissner–Nordström black hole is evenly spaced and the spacing is the same as that of a Schwarzschild black hole, which indicates that the area spectrum of a black hole is independent of its parameters. In contrast to quasi-normal mode analysis, we do not impose the small charge limit, as the general area gap 8π is obtained.