TEMPERATURE OF PERFECT FLUID BLACK HOLES IN VARIOUS COORDINATES AND ENTROPY COMPOSITION OF BLACK HOLE SYSTEMS

Abstract

The laws of thermodynamics describe the temperature and the entropy of perfect fluid black holes. The temperature can be calculated from the thermal radiation or Hawking radiation using surface gravity, while the entropy is related to the determined temperature. In this paper, we explain in detail the temperature and the entropy of black holes. Finally, we calculate the entropy composition of the perfect fluid black hole systems that have three black holes in the same coordinates. We are interested in two of these coordinates, the Schwarzschild coordinates and the isotropic coordinates, and will also analyze the two types of entropy compositions.