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arXiv · 2104.08091

Thermodynamics, photon sphere and thermodynamic geometry of Ayón-Beato-García Spacetime

Kartheek Hegde·A. Naveena Kumara·C. L. Ahmed Rizwan·Md Sabir Ali·Shreyas Punacha·K. M. Ajith
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Abstract

We study the thermodynamics of the Ayón-Beato-García black hole and the relationship between photon orbits and the thermodynamic phase transitions of the black hole in AdS spacetime. We then examine the interactions between the microstructures of the black hole using Ruppeiner geometry. The radius of the photon orbit and the minimum impact parameter behave non-monotonically below the critical point, mimicking the behaviour of Hawking temperature and pressure in extended thermodynamics. Their changes during the large black hole--small black hole phase transition serve as the order parameter, possessing a critical exponent of $1/2$. The results demonstrate that the gravity and thermodynamics of the Ayón-Beato-García black hole are closely related. Furthermore, we explore the thermodynamic geometry, which provides insight into the microstructure interactions of the black hole. We find that the large black hole phase is analogous to a bosonic gas with a dominant attractive interaction, while the small black hole phase behaves like an anyonic gas with both attractive and repulsive interactions.

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Kartheek Hegde, A. Naveena Kumara, C. L. Ahmed Rizwan, Md Sabir Ali, Shreyas Punacha, K. M. Ajith. 2025-10-07. Thermodynamics, photon sphere and thermodynamic geometry of Ayón-Beato-García Spacetime. https://doi.org/10.1142/s0217751x25501155

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