The gravitational Stefan-Boltzmann law is considered for the Kerr black hole in the weak-field limit. The energy-momentum tensor predicted by Teleparallelism Equivalent to General Relativity (TEGR) is used in the Thermo Field Dynamics (TFD) formalism to thermalize the field. A temperature-dependent gravitational pressure is obtained. Regions of divergent heat capacity are observed. According to Landau theory, it allows the existence of distinct phases around the Kerr black hole.
Comment: 15 pages, 04 figures, accepted for publication in Annalen der Physik