发表机构
Lanzhou University（兰州大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究在Rastall引力中分析带电Kiselev黑洞的轴向准正则模，发现物质响应与参考系统频率差异极小，且Rastall耦合和电荷对模频率及阻尼率有显著影响。
AI 中文摘要
我们研究了Rastall引力中由尘埃状Kiselev型各向异性物质包围的带电黑洞的轴向引力电磁准正则模。在忽略各向异性方向扰动的闭合方案下，系统简化为两个耦合的薛定谔型方程。这些方程在Reissner--Nordström极限和广义相对论尘埃状极限下允许r无关的代数解耦，但当Rastall修正和周围物质贡献同时存在时，这种解耦通常受阻。作为比较，我们引入了一个辅助的冻结源截断，其势矩阵与物质响应矩阵仅有两个条目不同。对于轴向偶极子，物质响应系统具有单向耦合，而截断参考系统具有双向耦合。尽管如此，物质响应系统和参考系统的代表性基频差异仅在亚百分比水平。通过Reissner--Nordström极限和谱收敛测试验证的Chebyshev伪谱计算表明，在小γ区域，增加无量纲Rastall耦合γ会降低振荡频率和阻尼率。在大γ区域，振荡频率上升，而阻尼率非单调变化。更大的黑洞电荷通常提高振荡频率，而更强的周围物质贡献倾向于产生更长寿命的模。所有调查的轴向基模满足Imω<0。
英文摘要
We investigate axial gravitoelectromagnetic perturbations of charged black holes surrounded by dust-like Kiselev-type anisotropic matter in Rastall gravity. We derive the axial matter compatibility condition and obtain two coupled Schrödinger-type master equations under a closure that neglects perturbations of the covariant anisotropy-direction vector. The equations admit an $r$-independent algebraic decoupling in the Reissner--Nordström and general-relativistic dust-like limits, whereas additional radial structure obstructs such a decoupling in generic charged Rastall backgrounds with nonzero surrounding matter. For the nonextremal backgrounds considered, we establish axial mode stability under this closure: a matrix $S$-deformation excludes exponentially growing coupled modes for $\ell\geq2$, and the physical electromagnetic dipole has a positive effective potential. A Chebyshev pseudospectral calculation, checked against the Reissner--Nordström spectrum and spectral convergence, characterizes the fundamental frequencies. Increasing the Rastall coupling lowers both the oscillation frequency and the damping rate in the small-coupling region; in the large-coupling region, the oscillation frequency rises while the damping rate varies nonmonotonically. A larger charge generally raises the oscillation frequency, whereas stronger surrounding-matter contributions tend to produce longer-lived modes. An auxiliary frozen-source truncation generally violates the matter constraint but yields sub-percent frequency differences for the representative configurations examined, showing that spectral proximity does not establish constraint compatibility.
Comments47 pages,6 figures,4 tables
