AI 中文总结
研究通过理想流体稀薄、稳定、球对称吸积增长的史瓦西黑洞的奇宇称衰荡，在吸积率一阶近似下直接计算时域衰荡波形，频率相关量能反映黑洞环境，多模式测量可约束黑洞周围环境。
AI 中文摘要
黑洞的衰荡波为强场引力提供了清晰的探测手段，但现实黑洞周围的物质分布使背景时空动态化，衰荡频率随时间变化。我们研究了通过理想流体的稀薄、稳定、球对称吸积而增长的史瓦西黑洞的奇宇称衰荡。在吸积率的一阶近似下，我们直接在这个动态背景上的时域中计算衰荡波形。由于奇宇称物质微扰与度规微扰解耦，波模式可以用吸积背景上的纯张量模式来描述。特别是，频率的虚部与实部之比消除了由黑洞增长引起的长期变化和红移因子，因此其与史瓦西值的偏差纯粹反映了周围环境。另一方面，频率的时间依赖性反映了吸积率，并使我们能够定义一个与之相关的第二个可观测值。我们认为，跨多个模式测量这些可观测值可能会提供重要信息，以约束黑洞的周围环境。
英文摘要
The ringdown waves from a black hole offer a clean probe of strong-field gravity, but a matter distribution that may be present around a realistic black hole renders the background spacetime dynamical and the ringdown frequencies time-dependent. We study the odd-parity ringdown of a Schwarzschild black hole that grows through the dilute, steady, spherically symmetric accretion of a perfect fluid. Working to first order in the accretion rate, we compute the ringdown waveform directly in the time domain on this dynamical background. Since the odd-parity matter perturbation decouples from the metric perturbation, the wave mode can be described by a purely tensorial mode on the accreting background. In particular, the ratio of the imaginary to the real part of the frequency cancels both the secular variation caused by the growth of the black hole and the redshift factor, so that its deviation from the Schwarzschild value purely reflects the surrounding environment. The time dependence of the frequency, on the other hand, reflects the accretion rate and allows us to define a second observable tied to it. We argue that measuring these observables across multiple modes may provide significant information to constrain the surrounding environment of the black hole.
Comments37 pages, 28 figures, 7 tables, references added
