Entropy of higher-dimensional charged de Sitter black holes and phase transition

TL;DR

This paper investigates the thermodynamic entropy and phase transitions of higher-dimensional Reissner-Nordström-de Sitter black holes, proposing an extra entropy term from horizon correlations and analyzing the system's thermodynamic behavior.

Contribution

It introduces a new entropy term accounting for horizon correlations and analyzes phase transitions in higher-dimensional RNdS black holes.

Findings

Extra entropy term improves thermodynamic description.

Phase transition behavior analogous to standard thermodynamic systems.

Effective temperature equality in lukewarm case facilitates analysis.

Abstract

From a new perspective, we discuss the thermodynamic entropy of $n+2$-dimensional Reissner-Nordstr\"om-de Sitter(RNdS) black hole and analyze the phase transition of the effective thermodynamic system. Considering the correlations between the black hole event horizon and the cosmological horizon, we conjecture that the total entropy of the RNdS black hole should contain an extra term besides the sum of the entropies of the two horizons. In the lukewarm case, the effective temperature of the RNdS black hole is the same as that of the black hole horizon and the cosmological horizon. Under this condition, we obtain the extra contribution to the total entropy. With the corrected entropy, we derive other effective thermodynamic quantities and analyze the phase transition of the RNdS black hole in analogy to the usual thermodynamic system.