Entanglement from the quantum internet to quantum neuroscience

纠缠是量子物理的一个独特特征。在经典物理学中，复合系统的动力学总是可以用它的组成部分来理解的。相比之下，纠缠的量子系统必须被视为一个完整的整体，即使它们相距数公里。这是新的量子应用的基础。长期愿景是建立在纠缠基础上的“量子互联网”，它承诺实现安全的量子通信，提高从原子钟网络到更好的望远镜等各种传感应用的精度，以及传统上无法获得的计算能力。本项目的一个主要部分是为这样的量子互联网设计蓝图和关键硬件元件。我的重点是固态体系结构，其中单个量子系统的自旋用于本地量子信息处理，而光子作为这些自旋之间的信息载体。(自旋是类似于经典角动量的独特量子特征，而光子是光的基本粒子。) 自旋和光子也是这个项目第二个主要部分的关键元素，该项目致力于“量子神经科学”，也就是量子纠缠是否可以在大脑中发挥作用的问题。调查这种可能性有两个主要动机。一方面，纠缠的整体性提供了一种独特的潜在解决方案，解决了我们的统一意识体验是如何从我们大脑中无数单个分子的动态中产生的问题(意识的“绑定问题”)。另一方面，量子技术具有独特的能力，这一事实使得人们自然会问，大自然是否也找到了利用这些效应进行信息处理的方法。在这种情况下考虑自旋和光子是很自然的，因为即使在高温的凝聚态环境中，它们也可以保持其量子性质。由于底层物理系统的这种共性，我的研究计划的两个部分之间有显著的协同效应。 这项拟议的研究将为基于纠缠的未来量子互联网的设计带来新的建议和原则性实验，这将使许多理想的量子应用程序能够增强我们的隐私、我们感知环境许多重要部分的能力以及我们的计算能力。这项研究还将提出新的建议和实验，解决纠缠等量子效应是否会在大脑中发挥作用的问题，这可能会让我们离理解意识的奥秘更近一步。

Entanglement is a unique feature of quantum physics. In classical physics the dynamics of a composite system can always be understood in terms of its parts. In contrast, entangled quantum systems have to be thought of as one integrated whole, even if they are kilometers apart. This is the foundation for new quantum applications. The long-term vision is a “quantum internet” based on entanglement which promises secure quantum communication, enhanced precision for various sensing applications ranging from atomic clock networks to better telescopes, and classically unattainable computing power. One main part of the present project is to design blueprints and key hardware elements for such a quantum internet. My focus is on solid-state architectures where the spins of individual quantum systems serve for local quantum information processing, while photons serve as information carriers between those spins. (Spin is a unique quantum feature similar to classical angular momentum, and photons are the elementary particles of light.) Spins and photons are also the key elements in the second main part of this project, which is dedicated to "quantum neuroscience", that is to the question whether quantum entanglement could play a role in the brain. There are two main motivations for investigating this possibility. On the one hand, the holistic character of entanglement provides a unique potential solution to the question how our unified conscious experience arises from the dynamics of myriads of individual molecules in our brains (the “binding problem” of consciousness). On the other hand, the fact that quantum technology has unique capabilities makes it natural to ask whether nature may also have found a way to harness these effects for information processing. It is natural to consider spins and photons in this context because they can preserve their quantum properties even in condensed-matter environments at high temperatures. As a consequence of this commonality in the underlying physical systems, there are significant synergies between the two parts of my research program. The proposed research will lead to new proposals and proof-of-principle experiments for the design of the future quantum internet based on entanglement, which will enable many desirable quantum applications that will enhance our privacy, our ability to sense many important parts of our environment, and our computing power. This research will also give rise to new proposals and experiments addressing the question whether quantum effects such as entanglement could play a role in the brain, which may bring us one step closer to understanding the mystery of consciousness.