After black holes collide, the remnant settles to a stationary state by emitting gravitational waves. Once nonlinearities subside, these ringdown waves are dominated by exponentially damped sinusoids, or quasinormal modes. We develop a general method using perturbative spectral expansions to calculate the quasinormal-mode frequencies and damping times in a wide class of modified gravity theories for black holes with any subextremal spin. We apply this method to scalar-Gauss-Bonnet gravity to show its accuracy, thus enabling robust ringdown tests with gravitational wave data.

中文翻译：

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响铃广义相对论：修正引力中任何自旋黑洞的准正态模态频率


黑洞碰撞后，残余物通过发射引力波稳定到静止状态。一旦非线性消退，这些振铃波就由指数阻尼的正弦波或准正则模态主导。我们开发了一种通用方法，使用扰动谱展开来计算具有任何亚极值自旋的黑洞的一大类修正引力理论中的准法态模式频率和阻尼时间。我们将该方法应用于标量-Gauss-Bonnet 引力，以证明其准确性，从而能够使用引力波数据进行稳健的振铃测试。