Thermodynamic geometry of the RN-AdS black hole and non-local observables

In this paper, we show the relation between the thermodynamic geometry of a four-dimensional Reissner-Nordstrom-AdS (RN-AdS) black hole and non-local observables in boundary field theory. Instead of introducing the critical point associating with the black hole charge to nondimensionalize the thermodynamics parameters, we use the cosmological constant to rescale these variables, so that a universal specific equation of state of the black hole is obtained. Further, the correspondence between thermodynamic properties of the black hole and the oscillating behaviors of the non-local observables has been studied numerically. Our results indicate that the study of the dual field theory will reveal to us the thermodynamic geometry of the AdS black hole.