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arXiv · 2411.09557

Mutual Influence of Photon Sphere and Non-Commutative Parameter in Various Non-Commutative Black Holes: Part I- Towards evidence for WGC

Mohammad Ali S. Afshar·Jafar Sadeghi
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Abstract

Non-commutative black holes(NCBH), due to the non-commutativity of spacetime coordinates, lead to a modification of the spacetime metric. By replacing the Dirac delta function with a Gaussian distribution, the mass is effectively smeared, eliminating point-like singularities. Our objective is to investigate the impact of this change on spacetime geodesics, including photon spheres and time-like orbits. We will demonstrate how the photon sphere can serve as a tool to classify spacetime, illustrating the influence of the NC parameter and constraining its values in various modes of these black holes. Additionally, using this classification, we will show how the addition of the nonlinear Einstein-Born-Infeld(BI) field to the model enhances its physical alignment with reality compared to the charged model. In the dS BI model, we will show how the study of the effective potential and photon sphere can provide insights into the initial structural status of the model, thereby establishing this potential as an effective tool for examining the initial conditions of black holes. Finally, by examining super-extremality conditions, we will show that the AdS BI model, with the necessary conditions, can be a suitable candidate for studying and observing the effects of the Weak Gravity Conjecture (WGC).

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Mohammad Ali S. Afshar, Jafar Sadeghi. 2024-11-14. Mutual Influence of Photon Sphere and Non-Commutative Parameter in Various Non-Commutative Black Holes: Part I- Towards evidence for WGC. https://doi.org/10.1016/j.dark.2025.101814

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