Critical behaviors and phase transitions of black holes in higher order gravities and extended phase spaces

Abstract

We consider the critical behaviors and phase transitions of Gauss–Bonnet–Born–Infeld-AdS black holes (GB–BI-AdS) for [Formula: see text] and the extended phase space. We assume the cosmological constant, [Formula: see text], the coupling coefficient [Formula: see text], and the BI parameter [Formula: see text] to be thermodynamic pressures of the system. Having made these assumptions, the critical behaviors are then studied in the two canonical and grand canonical ensembles. We find “reentrant and triple point phase transitions” (RPT-TP) and “multiple reentrant phase transitions” (multiple RPT) with increasing pressure of the system for specific values of the coupling coefficient [Formula: see text] in the canonical ensemble. Also, we observe a reentrant phase transition (RPT) of GB–BI-AdS black holes in the grand canonical ensemble and for [Formula: see text]. These calculations are then expanded to the critical behavior of Born–Infeld-AdS (BI-AdS) black holes in the third-order of Lovelock gravity and in the grand canonical ensemble to find a van der Waals (vdW) behavior for [Formula: see text] and a RPT for [Formula: see text] for specific values of potential [Formula: see text] in the grand canonical ensemble. Furthermore, we obtain a similar behavior for the limit of [Formula: see text], i.e. charged-AdS black holes in the third-order of the Lovelock gravity. Thus, it is shown that the critical behaviors of these black holes are independent of the parameter [Formula: see text] in the grand canonical ensemble.