论文标题
恩斯特黑洞中的带电标量场扰动
Charged scalar field perturbations in Ernst black holes
论文作者
论文摘要
我们考虑在四维Ernst黑洞的背景下进行带电的大规模标量场的传播，并研究其稳定性分析了准模式（QNM），该模式（QNM）是使用半分析性Gentzel-kramers-brillouin-brillouin方法计算的，并使用持续分数方法进行了计算。主要是，我们发现，对于标量场质量小于临界质量，当谐波角数$ \ ell $增加时，QNM的衰减速率会降低；对于标量场质量大于临界质量的质量，行为被反转，即，最长的模式始终是角度最低的恢复标准行为的模式。同样，我们发现外部磁场的临界值以及标量场电荷的临界值相对于角度谐波数具有相同的行为。此外，我们表明时空允许稳定的准圆形状态，并且由于Zeeman效应而观察到频谱的分裂。最后，我们证明赤道平面中的不稳定的无零用测量与QNM相连时，当方位角量子数满足eikonal限制中的$ m = \ pm \ ell $。
We consider the propagation of a charged massive scalar field in the background of a four-dimensional Ernst black hole and study its stability analyzing the quasinormal modes (QNMs), which are calculated using the semi-analytical Wentzel-Kramers-Brillouin method and numerically using the continued fraction method. Mainly, we find that for a scalar field mass less than a critical mass, the decay rate of the QNMs decreases when the harmonic angular number $\ell$ increases; and for a scalar field mass greater than the critical mass the behaviour is inverted, i.e, the longest-lived modes are always the ones with the lowest angular number recovering the standard behaviour. Also, we find a critical value of the external magnetic field, as well as, a critical value of the scalar field charge that exhibit the same behaviour with respect to the angular harmonic numbers. In addition, we show that the spacetime allows stable quasibound states and we observe a splitting of the spectrum due to the Zeeman effect. Finally, we show that the unstable null geodesic in the equatorial plane is connected with the QNMs when the azimuthal quantum number satisfy $m= \pm \ell$ in the eikonal limit.
