We study the response of a static Unruh-DeWitt detector outside an exotic compact object (ECO) in $3+1$ dimensions. The horizonless ECO, whose surface is extremely close to the would-be event horizon, acts as a black hole mimicker. ECOs that have an origin provide a physical means by which all waves, including gravitational waves, are reflected (off the origin). They also provide a source of damping of a wave as it traverses the material in the ECO. We study here the case of a probe scalar field for simplicity. We find that the response rate is notably distinct from the black hole case, even when the wave is lost completely to damping. For partial or no damping we find resonance structures in the response rate that depend on the compactness of the ECO and the detector location. We provide a detailed analysis in connection with the ECO’s vacuum mode structure and the transfer function.

中文翻译：

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Unruh-DeWitt 探测器对黑洞和奇异致密物体的区分

我们研究了外来紧凑物体 (ECO) 外的静态 Unruh-DeWitt 探测器的响应 $3+1$方面。无视界 ECO 的表面非常接近可能的事件视界，充当黑洞模拟者。具有原点的 ECO 提供了一种物理方法，通过该方法可以反射所有波，包括引力波（远离原点）。它们还提供了波在 ECO 中穿过材料时的阻尼源。为简单起见，我们在这里研究探针标量场的情况。我们发现响应率与黑洞情况明显不同，即使当波完全失去阻尼时也是如此。对于部分阻尼或无阻尼，我们发现响应速率中的共振结构取决于 ECO 的紧凑性和探测器位置。我们提供了与 ECO 的真空模式结构和传递函数相关的详细分析。