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arXiv · 1910.00939

Quasinormal modes of magnetized black hole

Bobur Turimov·Bobir Toshmatov·Bobomurat Ahmedov·Zden{ě}k Stuchlík
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Abstract

We investigate charged, massive scalar field around static, spherically symmetric black hole immersed into an external asymptotically uniform magnetic field $B$. It is shown that for given multipole number $\ell$ there are $2\ell+1$ numbers of modes due to the Zeeman effect appearing by an interaction of the external magnetic and charged scalar fields introducing an effective mass of the scalar field $\mu_{\rm eff}=\sqrt{\mu^2-mqB}$ where $m$ is the azimuthal number and $q$ is the charge coupling constant. We calculate threshold value of effective mass in which quasinormal modes are arbitrarily long lived and beyond that value quasinormal modes vanish. In the case of $m qB<0$ quasinormal modes are longer lived with larger oscillation frequencies. Whenever, magnetic and massive scalar fields satisfies condition $\mu_{\rm eff}^2<0$, an instability appears, i.e., if $qB>0$ or $qB<0$ there is an instability for the values of azimuthal number $m>\mu^2/qB$ or $m<\mu^2/qB$, respectively.

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Bobur Turimov, Bobir Toshmatov, Bobomurat Ahmedov, Zden{ě}k Stuchlík. 2019-10-02. Quasinormal modes of magnetized black hole. https://doi.org/10.1103/physrevd.100.084038

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