Thermodynamics of Reissner-Nordstrom-de Sitter black hole in York's formalism

By using York's path-integral formalism, we investigate the Reissner-Nordstrom-de Sitter (RNdS) spacetimes. We obtain not only the entropies of the lukewarm, the cold, the charged Nariai and the ultracold black holes, but also their first laws of thermodynamics. The entropy of the charged Nariai is given for the first time, to our knowledge.