We show that a signature of the quantum nature of gravity is the quantum mechanical squeezing of the differential motion of two identical masses with respect to their common mode. This is because the gravitational interaction depends solely on the relative position of the two masses. In principle, this squeezing is equivalent to quantum entanglement between the masses. In practice, detecting the squeezing is more feasible than detecting the entanglement. To that end, we propose an optical interferometric scheme to falsify hypothetical models of gravity.

中文翻译：

---

两个质量的微分运动中引力的量子性质的特征

我们表明引力的量子性质的一个特征是两个相同质量相对于它们的共模的微分运动的量子力学挤压。这是因为引力相互作用仅取决于两个质量的相对位置。原则上，这种挤压相当于质量之间的量子纠缠。在实践中，检测挤压比检测纠缠更可行。为此，我们提出了一种光学干涉测量方案来伪造假设的重力模型。