Hawking--Page phase transitions in four-dimensional Einstein--Gauss--Bonnet gravity

Understand

The Hawking-Page (HP) phase transitions of the anti-de Sitter black holes in the extended phase space are studied in a novel four-dimensional Einstein-Gauss-Bonnet (4EGB) gravity, which is proposed by rescaling the Gauss--Bonnet (GB) coupling constant $\alpha\to\alpha/(d-4)$ in $d$ dimensions and redefining the four-dimensional gravity in the limit $d \to 4$.

• The GB term shows nontrivial contributions to both black hole mass and entropy simultaneously, and decreases the HP phase transition temperature $T_{\rm HP}$.
• Moreover, the HP phase transitions can happen only within a range of pressure in the 4EGB gravity.
• For the charged black holes, $T_{\rm HP}$ also decreases with the electric potential in the grand canonical ensemble.