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Asymptotic quasinormal modes of a coupled scalar field in the Gibbons-Maeda dilaton spacetime

Songbai Chen·Jiliang Jing
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Abstract

Adopting the monodromy technique devised by Motl and Neitzke, we investigate analytically the asymptotic quasinormal frequencies of a coupled scalar field in the Gibbons-Maeda dilaton spacetime. We find that it is described by $ e^{βω}=-[1+2\cos{(\frac{\sqrt{2ξ+1}}{2} π)}]-e^{-β_I ω}[2+2\cos{(\frac{\sqrt{2ξ+1}}{2}π)}]$, which depends on the structure parameters of the background spacetime and on the coupling between the scalar and gravitational fields. As the parameters $ξ$ and $β_I$ tend to zero, the real parts of the asymptotic quasinormal frequencies becomes $T_H\ln{3}$, which is consistent with Hod's conjecture. When $ξ={91/18} $, the formula becomes that of the Reissner-Nordström spacetime.

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Songbai Chen, Jiliang Jing. 2005-11-18. Asymptotic quasinormal modes of a coupled scalar field in the Gibbons-Maeda dilaton spacetime. https://doi.org/10.1088/0264-9381%2F22%2F11%2F016

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