相对论量子信息和量子引力研究中的量子关联和非定域性

As a combination of general relativity, black hole physics, cosmology and quantum information theory, Relativistic Quantum Information (RQI) has been a new fast-growing research field in recent years. This project is devoted to explore various RQI topics for multipartite and observable quantum systems. In particular, we will focus on the quantum uncertainty relations, as an entanglement witness, and investigate how the system’s acceleration, Unruh-Hawking effect, cosmological horizon, gravitational waves and quantum gravity at Planck-scale can influence the uncertainty bound and quantum metrology in relativistic frames. We will investigate the dynamical evolution of quantum correlations generated in Unruh-Dewitt detector and accelerated rigid cavity, and its profound relation with curved spacetime background and relativistic motion of system. Employing the CHSH/Leggett-Garg inequalities in curved space, we will explore the generation and evolution of quantum nonlocality in cosmology which could be used to explain the quantum-classical transition in early universe. We will also study the continuous quantum information issues in relativistic frame, including the witness of quantum correlation (quantum uncertainty bound), nonlocality and quantum decoherence. The conduction of this project will not only provide a more complete understanding on quantum information theory and general relativity, but can also shed new light on related topics like black hole information paradox, dark matter and dark energy, and quantum metrology applied in the detection of gravitational wave.

作为广义相对论、黑洞物理、宇宙学和量子信息学的交叉学科，近几年来相对论框架下量子信息学已成为物理学研究的新热点。本项目致力于研究多体和可观测量子系统的相对论量子信息问题。将以量子不确定边界作为量子关联度量，探讨加速度、Hawking效应、宇宙学视界、引力波和Planck尺度的量子引力对量子测量不确定边界的影响；研究Unruh-Dewitt探测器或腔场等局域量子系统中纠缠的动力学演化与弯曲时空背景及相对论运动的内在联系；利用弯曲空间中CHSH/LG判别式，研究宇宙学背景中量子非定域性的形成和演化，理解早期宇宙中量子－经典转换；研究相对论框架下的连续变量量子信息学，包括对应的量子关联（量子不确定边界）、非定域性和退相干等问题。该项目的研究对量子信息理论和相对论理论的进一步发展和完善有十分重要的意义，并将对黑洞信息佯谬、暗物质和暗能量、引力波探测等问题的解决起到积极的推动作用。

作为广义相对论、黑洞物理、宇宙学和量子信息学的交叉学科，近几年来相对论框架下量子信息学已成为物理学研究的新热点。本项目致力于研究多体和可观测量子系统的相对论量子信息问题，研究发现：（1）以细粒化量子不确定边界作为量子关联度量，全局模态和局域腔场模态构成的量子系统在Unruh退相干下行为完全不同。特别是腔场的不确定边界随腔加速度成周期变化。选取合适腔的几何构型，可以屏蔽Unruh退相干对不确定边界的放大（2）发现在宇宙学背景中的量子精密测量极限和时空曲率及早期宇宙初始条件的关系。发现极大Fisher信息只出现在探测器的特定初态。并且，对具有非 Bunch-Davies (BD) 初始条件的宇宙，能得到更大的量子 Fisher 信息（3）采用 CHSH 不等式违反来判定具有非 BD 真空的宇宙中开放量子系统的非定域性。发现量子系统 Markovian 演化产生的非定域性在非 BD 情形中随时空曲率增大具有非单调行为。即使在无穷大曲率极限，CHSH 不等式依然可被违反，这和过去人们对此的认知完全不同。