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arXiv · 2507.22673

Photon Deflection and Magnification in Kalb-Ramond Black Holes with Topological String Configurations

Faizuddin Ahmed·İzzet Sakallı·Ahmad Al-Badawi
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Abstract

This theoretical investigation examines gravitational lensing phenomena in Schwarzschild-like black holes (BHs) within Kalb-Ramond (KR) gravity frameworks incorporating cosmic string (CS) and cloud of strings (CoS) topological configurations. We develop comprehensive analytical methodologies for investigating photon deflection angles and magnification characteristics in both Schwarzschild-like BHs in KR gravity pierced by CSs (SKRCS) and Schwarzschild-like BHs in KR gravity with CoS (SKRCoS) spacetime geometries through dual approaches: perturbative expansions yielding approximate solutions and exact elliptic integral formulations providing complete mathematical descriptions across parameter spaces. For CS configurations characterized by Lorentz violation (LV) and CS parameters, deflection angles exhibit systematic modifications through composite geometric factors, while CoS geometries demonstrate distinct deflection characteristics incorporating additional topological parameters that fundamentally alter light propagation dynamics. Magnification analysis reveals distinctive critical curve positioning modifications and amplitude scaling relationships enabling observational discrimination between exotic BH scenarios and conventional spacetime geometries. Strong field analysis utilizing established mathematical frameworks establishes logarithmic divergence coefficients characterizing fundamental scaling behavior in photon sphere proximity regimes. Observational constraints from Solar System precision tests restrict LV parameters within stringent bounds, while galactic-scale observations permit expanded parameter ranges for CS and CoS configurations.

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Faizuddin Ahmed, İzzet Sakallı, Ahmad Al-Badawi. 2025-07-30. Photon Deflection and Magnification in Kalb-Ramond Black Holes with Topological String Configurations. https://arxiv.org/abs/2507.22673

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