Intriguing microstructures of five-dimensional neutral Gauss-Bonnet AdS black hole

TL;DR

This paper explores the microstructure and phase transitions of five-dimensional neutral Gauss-Bonnet AdS black holes, revealing consistent microscopic interactions across phase transitions through Ruppeiner geometry analysis.

Contribution

It analytically constructs the Ruppeiner geometry for the black hole, uncovering invariant microstructural interactions before and after phase transitions.

Findings

Attractive interactions dominate the microstructure.

Normalized scalar curvature is identical for small and large black holes.

Microstructure interactions remain unchanged across phase transition.

Abstract

In this paper, we analytically study the phase structure and construct the Ruppeiner geometry in the extended phase space for the five-dimensional neutral Gauss-Bonnet AdS black hole. Through calculating the scalar curvature of the Ruppeiner geometry and combining the phase transition, we show that the attractive interaction is dominant in the microstructure of the black hole system. More significantly, there is an intriguing property that the normalized scalar curvature has the same expression for the saturated small and large black hole curves. This implies that although the microstructure is different before and after the small-large black hole phase transition, the interaction between the microscopic constituents keeps unchanged. These results are quite valuable on further understanding the microstructure of the AdS black hole in modified gravity.