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arXiv · 2504.04331

Shedding Light on Gravity: Black Hole Shadows and Lensing Signatures in Lorentz Gauge Theory

Ali Övgün·Mohsen Fathi
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Abstract

Recent advances, including gravitational wave detections and imaging of black hole shadows, have strongly validated general relativity. Nevertheless, ongoing cosmological observations suggest potential limitations of general relativity, spurring interest in modified theories of gravity. This work investigates the Lorentz-gauge formulation of gravity-a novel framework that addresses key conceptual challenges in quantum gravity and cosmology by leveraging the recent black hole solutions presented in Ref. \cite{Koivisto:2024asr}. By analyzing black hole shadow structures and gravitational lensing effects-both weak and strong deflection regimes-we highlight unique observational signatures of Lorentz gauge gravity. Our findings provide valuable tools for future observational tests, potentially distinguishing these modified gravity models from general relativity and advancing our understanding of spacetime geometry and fundamental gravitational interactions.

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Ali Övgün, Mohsen Fathi. 2025-04-06. Shedding Light on Gravity: Black Hole Shadows and Lensing Signatures in Lorentz Gauge Theory. https://doi.org/10.1016/j.nuclphysb.2025.117063

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