The microstructure and Ruppeiner geometry of charged anti-de Sitter black holes in Gauss-Bonnet gravity: from the critical point to the triple point

Abstract

Ruppeiner geometry has been successfully applied in the study of the black hole microstructure by combining with the small-large black hole phase transition, and the potential interactions among the molecular-like constituent degrees of freedom are uncovered. In this paper, we will extend the study to the triple point, where three black hole phases coexist acting as a typical feature of black hole systems quite different from the small-large black hole phase transition. For the six-dimensional charged Gauss-Bonnet anti-de Sitter black hole, we thoroughly investigate the swallow tail behaviors of the Gibbs free energy and the equal area laws. After obtaining the black hole triple point in a complete parameter space, we exhibit its phase structures both in the pressure-temperature and temperature-horizon radius diagrams. Quite different from the liquid-vapor phase transition, a double peak behavior is present in the temperature-horizon radius phase diagram. Then we construct the Ruppeiner geometry and calculate the corresponding normalized curvature scalar. Near the triple point, we observe multiple negatively divergent behaviors. Positive curvature scalar is observed for the small black hole with high temperature, which indicates that the repulsive interaction dominates among the microstructure. Furthermore, we consider the variation of the curvature scalar along the coexisting intermediate and large black hole curves. Combining with the observation for different fluids, the result suggests that this black hole system behaves more like the argon or methane. Our study provides a first and preliminary step towards understanding black hole microstructure near the triple point, as well as uncovering the particular properties of the Gauss-Bonnet gravity.

17 pages, 11 figures, and 1 table

References in corpus (17)

• Multiple Reentrant Phase Transitions and Triple Points in Lovelock Thermodynamics
• Critical phenomena and thermodynamic geometry of charged Gauss-Bonnet AdS black holes
• Superfluid Black Holes
• Extended phase space thermodynamics for third order Lovelock black holes in diverse dimensions
• Isolated critical point from Lovelock gravity
• Critical behaviour and microscopic structure of charged AdS black holes via an alternative phase space
• Clapeyron equations and fitting formula of the coexistence curve in the extended phase space of charged AdS black holes
• Intriguing microstructures of five-dimensional neutral Gauss-Bonnet AdS black hole
• Observing dynamic oscillatory behavior of triple points among black hole thermodynamic phase transitions
• Ruppeiner Geometry, Phase Transitions and Microstructures of Black Holes in Massive Gravity
• Phase transition and microstructures of five-dimensional charged Gauss-Bonnet-AdS black holes in the grand canonical ensemble
• Coexistent Physics and Microstructure of the Regular Bardeen Black Hole in Anti-de Sitter Spacetime
• Divergence Behavior of Thermodynamic Curvature Scalar at Critical Point in the Extended Phase Space of Generic Black Holes
• Thermodynamic curvature of the binary van der Waals fluid
• Fluctuations and thermodynamic geometry of the chiral phase transition
• Analytic phase structures and thermodynamic curvature for the charged AdS black hole in alternative phase space
• Testing the microstructure of $d$-dimensional charged Gauss-Bonnet anti-de Sitter black holes

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• Thermodynamically Stable Phases of Asymptotically Flat Lovelock Black Holes
• The Kramers escape rate of phase transitions for the 6-dimensional Gauss-Bonnet AdS black hole with triple phases