International Quantum Tensor Network

该项目的目的是形成一个国际合作网络，任务是创建一种基于使用张量网络为量子计算机编写软件的新方法。张量网络是在经典计算机上模拟量子系统的最佳方法之一。量子系统的可能性是如此之多，以至于它们不能在任何经典计算机上全部描述。这是一个意义深远的问题——从描述30个量子自旋（大约是当今超级计算机的极限）到31个，计算需求翻了一番，因此不断发展的传统硬件无法跟上我们想要解决的问题。张量网络通过关注系统中真正重要的部分来解决这个问题，这样我们就可以得到一个近似的——但高度准确的——描述，随着我们的计算机变得更好，我们可以系统地改进这个描述。量子力学中一些最精确的预测就是用这种方法做出的。张量网络也是利用短期中等规模量子（NISQ）计算机上有限的可用量子资源的一种极好的方式。由于环境对量子相关性的退化效应，这些计算机的功率有限——通过量子系统的一种被称为纠缠的特性来衡量。张量网络精确地使用这种纠缠度量来确定如何近似量子系统的最重要属性，正是由于这个原因，它们是编程量子计算机的好方法。这种量子软件的方法才刚刚开始开发，但已经显示出良好的前景。国际量子张量网络旨在将英国置于进一步发展该方法的国际推动的中心。这种量子软件的应用将有助于使用量子计算机来模拟其他量子系统，最终有望彻底改变化学和药物设计中的量子问题，同时也能解决包括机器学习在内的各种经典问题。

The aim of this project is to form a network of international collaboration tasked with creating a new way to write software for quantum computers based upon using tensor networks.Tensor networks are amongst the very best ways to model quantum systems on a classical computer. The possibilities for a quantum system are so numerous that they cannot all be described on any classical computer. The problem is a profound one - to go from describing 30 quantum spins (around the limit for today's supercomputers) to 31 doubles the computational requirements, so evolving conventional hardware cannot keep up with the problems that we want to solve. Tensor networks get round this by focusing on the parts of the system that really matter so that we can get an approximate - but highly accurate - description that we can systematically improve as our computer gets better. Some of the most accurate predictions in quantum mechanics have been made using this approach.Tensor networks are also an excellent way of making use of the limited quantum resources available on near term intermediate-scale quantum (NISQ) computers.These computers have limited power - measured by a property of quantum systems known as entanglement - due to the degrading effect that the environment has on quantum correlations. Tensor networks use precisely this entanglement measure to determine how to approximate the most important properties of the quantum system, and it is for this reason that they are such a good way to programme quantum computers. This approach to quantum software has just begun to be developed, but already shows excellent promise. The International Quantum Tensor Network is designed to place the UK at the centre of an international push to further develop the approach. The applications of this quantum software will help to use quantum computers to simulate other quantum systems - with the promise ultimately to revolutionise quantum problems in chemistry and drug design - but also to solve a variety of classical problems including those in machine learning.