Effect of the inner horizon on the black hole thermodynamics: Reissner–Nordström black hole and Kerr black hole

For the Schwarzschild black hole, Bekenstein–Hawking entropy is proportional to area of event horizon. holes with two horizons, thermodynamics not very clear, since role inner horizons well established. Here we calculate Reissner–Nordström hole and Kerr which have horizons. spherically symmetric used several different approaches. All them give same result for corresponding temperature thermal Hawking radiation. The determined by outer horizon, it equal sum entropies It correlations between due total radiation depend only on mass M do charge Q. Kerr–Newman holes, shown that their has similar property: depends does angular momentum J