Gravity Induced Quantum Entanglement: Methodologies & Noise Control

引力是否是一种量子力，目前还不得而知。虽然有相当多的量子引力理论，它们在低能极限下都是一致的，并与观测结果一致，但对于引力是否为量子，仍然没有经验证据。考虑到这一点，在这个项目中，我们将致力于改进一类拟议的实验，在低能量限制下工作，可以证明引力是否本质上是量子的。这类实验是基于两个相邻的质量纯粹通过它们的引力相互作用来纠缠。由于经典介体不能将两个质量纠缠在一起(可以用几种方式来证明这一点)，对纠缠的观察将证明引力是量子的。目前的项目将寻求(I)创造稳健的方法，在两个不同的地方产生大质量的叠加--例如，涉及嵌入在宏物体中的许多自旋。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的退相干的稳健性和容忍性，并将使用量子控制方案来增强稳健性。(Iii)将制定使用额外的传感器来检测和考虑环境噪声。

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.