Extended Phase Space Thermodynamics and Joule-Thomson Expansion of Regular AdS Black Holes in a String Cloud

Abstract

We investigate the extended phase space thermodynamics of a static, spherically symmetric regular black hole immersed in a string cloud background. By identifying the negative cosmological constant as a thermodynamic pressure, our analysis indicates that the quantum-inspired regularizing core and the string cloud density significantly affect the thermal stability of the black hole. We specifically illustrate a stringent scale invariance linked to the regularizing core, while the dimensionless string cloud parameter substantially alters the universal Van der Waals critical compressibility ratio. The significant geometric inconsistencies result in computed critical exponents that align with those of mean-field theory. We specify the Joule-Thomson expansion to define the isenthalpic heating and cooling regimes, so providing a comprehensive thermodynamic characterization of this non-singular spacetime.