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arXiv · 2609.31227

Charged Letelier--Alencar Black Strings with a Quintessence and the Cosmolgical Constant

B. Eslam Panah·F. M. da Silva·L. G. Barbosa
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Abstract

This study derives charged black string solutions in the presence of a Letelier--Alencar cloud of strings and quintessence within Einstein--Maxwell--$Λ$ theory. We study the curvature scalars in order to investigate the asymptotical behavior of these solutions. We calculate the relevant conserved and thermodynamic quantities, confirming their compliance with the first law of thermodynamics. System stability is rigorously analyzed through heat capacity and Gibbs free energy, identifying regimes of local and global equilibrium. Additionally, by interpreting the cosmological constant as thermodynamic pressure within an extended phase space, we establish the validity of the extended first law and derive the corresponding Smarr relation for these solutions. We also investigate the null geodesic structure, deriving the equation for the photon cylinder radius, which generalizes the known result for charged black strings by incorporating the effects of the Letelier--Alencar cloud of strings and quintessence. The numerical analysis of this equation determines the existence and location of photon cylinders as functions of the model parameters.

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B. Eslam Panah, F. M. da Silva, L. G. Barbosa. 2026-09-25. Charged Letelier--Alencar Black Strings with a Quintessence and the Cosmolgical Constant. https://arxiv.org/abs/2609.31227

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