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Logarithmic perturbation theory for quasinormal modes

P. T. Leung·Y. T. Liu·W. M. Suen·C. Y. Tam·K. Young
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Abstract

Logarithmic perturbation theory (LPT) is developed and applied to quasinormal modes (QNMs) in open systems. QNMs often do not form a complete set, so LPT is especially convenient because summation over a complete set of unperturbed states is not required. Attention is paid to potentials with exponential tails, and the example of a Poschl-Teller potential is briefly discussed. A numerical method is developed that handles the exponentially large wavefunctions which appear in dealing with QNMs.

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P. T. Leung, Y. T. Liu, W. M. Suen, C. Y. Tam, K. Young. 1997-12-18. Logarithmic perturbation theory for quasinormal modes. https://doi.org/10.1088/0305-4470/31/14/013

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