发表机构
College of Physics and Optoelectronic Engineering, Chongqing Normal University; School of Big Data and Artificial Intelligence, Fuyang University of Technology; Universidade Federal de Campina Grande; Instituto de Física, Universidade de São Paulo; Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences（重庆师范大学物理与电子工程学院; 阜阳工业大学大数据与人工智能学院; 坎皮纳格兰德联邦大学; 圣保罗大学物理研究所; 中国科学院力学研究所微重力国家实验室引力波实验中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过将视界量子退相干映射为有效反射率，利用Kerr射线追踪和ACF流程，证明黑洞回波可观测，为检验黑洞幺正性提供可行途径。
AI 中文摘要
黑洞的几何阴影无法在观测上区分无视界的奇异致密天体。我们通过将视界的基本量子退相干机制（Danielson-Satishchandran-Wald机制）映射为宏观有效反射率$\mathcal{R}$来打破这一简并性。利用Kerr射线追踪，我们表明在镜面反射和漫反射（朗伯）条件下，部分反射边界（$\mathcal{R}>0$）会产生延迟的电磁回波。在空间域中，这些回波照亮了内部阴影并改变了低频可见度，同时保持由度规支配的光子子环不变。信号强度随膜致密性$\epsilon$按$\epsilon^{\Gamma}$缩放，其中镜面反射时$\Gamma=0$，而由于逃逸锥坍缩，漫反射再发射时$\Gamma\to1$。这使得镜面反射率降至$\mathcal{R}\simeq0.12$（ngEHT）和$0.04$（BHEX），处于静态成像的探测范围内。对于人马座A$^\ast$，我们将这些回波转化为稳健的时域特征。利用自相关函数（ACF）流程，我们证明单次耀发回波可以从严重的吸积红噪声中干净地提取，在15至33小时的连续监测中，对振幅$\mathcal{A}\gtrsim0.3$实现$3\sigma$探测。该框架为检验黑洞幺正性提供了一条可直接部署的路径。
英文摘要
The geometric shadow of a black hole cannot observationally distinguish horizonless exotic compact objects. We break this degeneracy by mapping the fundamental quantum decoherence of the horizon (the Danielson-Satishchandran-Wald mechanism) into a macroscopic effective reflectivity $\mathcal{R}$. Utilizing Kerr ray tracing, we show that a partially reflective boundary ($\mathcal{R}>0$) generates delayed electromagnetic echoes under both specular and diffuse (Lambertian) conditions. In the spatial domain, these echoes illuminate the inner shadow and alter low-frequency visibilities, while leaving metric-governed photon subrings unchanged. The signal strength scales with the membrane compactness $ε$ as $ε^Γ$, where $Γ=0$ for specular reflection and $Γ\to1$ for diffuse re-emission due to escape-cone collapse. This brings specular reflectivities down to $\mathcal{R}\simeq0.12$ (ngEHT) and $0.04$ (BHEX) within reach of static imaging. For Sagittarius A$^\ast$, we translate these echoes into a robust time-domain signature. Using an Autocorrelation Function (ACF) pipeline, we demonstrate that single-flare echoes can be cleanly extracted from severe accretion red noise, achieving a $3σ$ detection for amplitudes $\mathcal{A}\gtrsim0.3$ within 15 to 33 hours of continuous monitoring. This framework provides a directly deployable pathway to test black hole unitarity.
Comments18 pages, 11 figures
