Gravity Induced Quantum Entanglement: Methodologies & Noise Control

目前尚不清楚引力是否是一种量子力学力。虽然有相当多的量子引力理论，它们都在低能极限下相互一致，并且与观测相一致，但关于引力是否量子，仍然没有经验证据。考虑到这一点，在这个项目中，我们将努力完善一类拟议的实验，这些实验在低能量极限下工作，可以证明重力在本质上是否基本上是量子的。这类实验的基础是纯粹通过引力相互作用使两个附近的质量相互纠缠。由于经典介质不能使两个质量纠缠在一起（可以用几种方法来证明），对纠缠的观察将证明引力是量子的。目前的项目将寻求(i)创建可靠的方法来在两个不同的地方产生大质量的叠加——例如，在宏观物体中嵌入许多自旋。这些将被用来产生和证明引力纠缠。（ii）将研究这些方案对环境诱导退相干的鲁棒性和容忍度，并使用量子控制方案来增强鲁棒性。（iii）将拟订使用额外的传感器来探测和考虑环境噪音。

It is still not known whether gravity is a quantum mechanical force. Although there are quite a few theories of quantum gravity, which all agree with each other in the low energy limit and are consistent with observations, there is still no empirical proof as to whether gravity is quantum. With this in mind, in this project, we will work towards refining a class of proposed experiment, which, while working in the low energy limit, can certify whether gravity is fundamentally quantum in nature. These class of experiments are based on entangling two nearby masses purely through their gravitational interaction. As a classical mediator cannot entangle two masses (can be justified in several ways), an observation of entanglement will certify gravity to be quantum. The current project will seek to(i) Create robust ways to generate superpositions of a large mass in two distinct places -- for example involving many spins embedded inside macro-objects. These will be then used to generate and evidence the gravitational entanglement.(ii) The robustness and tolerance of such schemes to environment induced decoherence will be studied and quantum control schemes will be used to enhance the robustness.(iii) Usage of additional sensors to detect and take into account the ambient noise will be formulated.