In this letter we consider the exact solution of the Klein-Gordon equation describing a massless scalar field in the spacetime of a four dimensional canonical acoustic black hole, which is given in terms of the general Heun function, to discuss the interesting phenomena related to the resonant frequencies.

中文翻译：

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标准声学黑洞时空中无质量标量场的共振频率

在这封信中，我们考虑了描述四维经典声学黑洞时空中无质量标量场的 Klein-Gordon 方程的精确解，该方程根据一般 Heun 函数给出，以讨论与共振频率。