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arXiv · 2505.13833

AdS Black String in a Cosmic Web: Geodesics, Shadows, and Thermodynamics

Faizuddin Ahmed·Ahmad Al-Badawi·Izzet Sakallı
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Abstract

In a recent article (Ref. \cite{AOP}), the authors obtained a static, cylindrically symmetric Anti-de Sitter (AdS) black string (BS) solutions, which are cylindrical generalizations of black holes (BHs), surrounded by a cloud of strings (CS) and the quintessence field (QF), and discussed its properties. In the present study, we present a comprehensive analysis of cylindrically symmetric AdS BSs surrounded by CS and QF. Our analysis yields several significant results. We demonstrate that the presence of CS (parameter $α$) and QF (parameters $c$ and $w$) reduces the radius of circular photon orbits (CPO) and BH shadow size, with measurements constrained by Event Horizon Telescope (EHT) observations of Sagittarius A*. We find that time-like particle orbits show increased energy with higher $α$ and $c$ values. We calculate that C-energy, representing gravitational energy within cylindrical radius, decreases with radial distance but exhibits distinct responses to CS and QF parameters. We observe that scalar perturbation potential increases $r$ for specific $α$ and $c$ values, indicating stronger field-spacetime interactions away from the BS. We determine that Hawking temperature increases linearly with Schwarzschild radius, with parameter-dependent behavior varying based on QF state parameter $w$. These results demonstrate how CS and QF significantly modify the geodesic, perturbative, and thermodynamic properties of AdS BS, with potential observational implications for gravitational lensing, accretion disk dynamics, and BH evaporation signatures in future astronomical observations.

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Faizuddin Ahmed, Ahmad Al-Badawi, Izzet Sakallı. 2025-05-20. AdS Black String in a Cosmic Web: Geodesics, Shadows, and Thermodynamics. https://doi.org/10.1140/epjc%2Fs10052-025-14266-y

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