论文标题
重力场中的量子时间扩张
Quantum time dilation in a gravitational field
论文作者
论文摘要
根据相对论，理想时钟的读数被解释为沿其经典轨迹通过时空的适当时间。相比之下，量子理论允许许多同时轨迹与单个量子时钟的关联，每个时钟都适当加权。在这里，我们研究了叠加原理如何影响一个简单的时钟观察到的重力时间扩张 - 腐烂的两级原子。将这种原子放置在位置的叠加中，使我们能够分析自发发射中经典时间扩张的量子贡献。特别是，我们表明，在重力场中分离波包的相干叠加中制备的原子的发射速率与这些数据包的经典混合物中原子的发射速率不同，这产生了量子重力时间扩张效应。我们证明，这种非经典效应也表现出在当前原子钟的分辨率内的原子内部能的分数转移中。此外，我们还显示了空间相干性对原子发射光谱的影响。
According to relativity, the reading of an ideal clock is interpreted as the elapsed proper time along its classical trajectory through spacetime. In contrast, quantum theory allows the association of many simultaneous trajectories with a single quantum clock, each weighted appropriately. Here, we investigate how the superposition principle affects the gravitational time dilation observed by a simple clock - a decaying two-level atom. Placing such an atom in a superposition of positions enables us to analyze a quantum contribution to a classical time dilation manifest in spontaneous emission. In particular, we show that the emission rate of an atom prepared in a coherent superposition of separated wave packets in a gravitational field is different from the emission rate of an atom in a classical mixture of these packets, which gives rise to a quantum gravitational time dilation effect. We demonstrate that this nonclassical effect also manifests in a fractional frequency shift of the internal energy of the atom that is within the resolution of current atomic clocks. In addition, we show the effect of spatial coherence on the atom's emission spectrum.
