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arXiv · 2411.08564

Shadow analysis of an approximate rotating black hole solution with weakly coupled global monopole charge

Mohsen Fathi
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Abstract

We investigate the shadow properties of a rotating black hole with a weakly coupled global monopole charge, using a modified Newman-Janis algorithm. This study explores how this charge and rotational effects shape the black hole's shadow, causal structure, and ergoregions, with implications for distinguishing it from Kerr-like solutions. Analysis of null geodesics reveals observable features that may constrain the global monopole charge and weak coupling parameters within nonminimal gravity frameworks. Observational data from M87* and Sgr A* constrain the global monopole charge and coupling constant to $0 \leq \gamma \lesssim 0.036$ and $-0.2 \lesssim \alpha \leq 0$, respectively.

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Mohsen Fathi. 2024-11-13. Shadow analysis of an approximate rotating black hole solution with weakly coupled global monopole charge. https://doi.org/10.3390/universe11040111

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