Kiselev black strings in $f(R,T)$ gravity

TL;DR

This paper derives and analyzes static and rotating black string solutions in $f(R,T)$ gravity with quintessence matter, exploring their energy conditions, thermodynamics, and stability, revealing how matter and modified gravity influence their properties.

Contribution

It presents new exact black string solutions in $f(R,T)$ gravity with anisotropic matter and studies their physical and thermodynamic properties.

Findings

Solutions satisfy energy conditions in specific parameter regions

Hawking temperature and heat capacity are derived for these black strings

Conditions for thermodynamic stability and phase transitions are identified

Abstract

In this work, we investigate exact black string solutions in the context of $f(R,T)$ gravity. Adopting the specific form $f(R,T) = R + 2\chi T$, we consider an anisotropic Kiselev fluid as the matter content and obtain static cylindrical solutions, which are then extended to the rotating case through a suitable coordinate transformation. The influence of the quintessence state parameter $w_q$ and the matter--geometry coupling constant $\chi$ on the geometry is analyzed. We examine the weak, null, and strong energy conditions, identifying the regions in the parameter space where they are satisfied. Furthermore, we apply the Hamilton--Jacobi method to study the tunneling of scalar particles across the event horizon and derive the corresponding Hawking temperature. The thermodynamic stability of the solutions is investigated by computing the heat capacity, and the conditions for phase transitions are discussed. The results provide a characterization of black strings in $f(R,T)$ gravity surrounded by quintessence, highlighting the combined effects of anisotropic matter and modified gravity on their physical properties.