Computer-aided cluster expansion: An efficient algebraic approach for open quantum many-particle systems

We introduce an equation of motion approach that allows for an approximate evaluation of the time evolution of a quantum system, where the algebraic work to derive the equations of motion is done by the computer. The introduced procedures offer a variety of different types of approximations applicable for finite systems with strong coupling as well as for arbitrary large systems where augmented mean-field theories like the cluster expansion can be applied.我们提出了一种运动方程(equation of motion)方法，可用于近似求解量子系统(quantum system)的时间演化过程，其中推导运动方程所需的代数运算由计算机完成。所提出的这套方法提供了多种不同类型的近似方案，既适用于强耦合有限系统，也可用于任意规模的大型系统——这类系统可应用集团展开(cluster expansion)等拓展平均场理论(augmented mean-field theories)。