To answer the question posed in the title, we consider a novel diagnostic, viz., the difference in the time of arrival (TOA) at the observer of two light rays that simultaneously emanate from a source behind a spinning lens and pass by either side of the lens to reach the observer. This is completely different from the usual Shapiro gravitational time delay, where only one onward light ray is reflected back to the observer. The TOA essentially samples the frame dragging caused by the spinning lens, apart from other lens parameters. Assuming a charged regular Ayón-Beato and García black hole as the spinning lens partner in some typical astrophysical pulsar black hole (PSR-BH) binaries, which provide the best laboratory for testing the TOA effect, we theoretically study how the prediction depends on the gyromagnetic ratio \(\left( Q/M\right) \) and how it compares with those when the role of spinning lens partner is played by the centrally singular Kerr–Newman and Kerr black holes. The numerical estimates for two illustrative binary lens systems show microsecond-level delay at the zeroth order, which should be measurable. However, the TOA predictions under thin-lens approximation are shown to differ only at third or higher orders of smallness indicating that the regular and singular black holes cannot be observationally distinguished despite significant qualitative differences existing among them.

为了回答标题中提出的问题，我们考虑了一种新颖的诊断方法，即观察者同时从旋转透镜后面的光源发出并经过任一侧的两条光线的到达时间 (TOA) 差异镜头到达观察者。这与通常的夏皮罗引力时间延迟完全不同，后者只有一条向前的光线被反射回观察者。除其他镜头参数外，TOA 基本上对由旋转镜头引起的帧拖拽进行采样。假设一个带电的常规 Ayón-Beato 和 García 黑洞作为一些典型的天体物理脉冲星黑洞 (PSR-BH) 双星中的旋转透镜伙伴，为测试 TOA 效应提供了最好的实验室，我们从理论上研究了预测如何取决于旋磁比\(\left( Q/M\right) \)以及它与旋转透镜伙伴的角色由中心奇异的 Kerr-Newman 和 Kerr 黑洞进行比较时的情况。两个说明性二元透镜系统的数值估计显示零阶微秒级延迟，这应该是可测量的。然而，薄透镜近似下的 TOA 预测显示仅在三阶或更高阶的小量级上有所不同，这表明尽管规则黑洞和奇异黑洞之间存在显着的质量差异，但在观察上无法区分。