Abstract
The aim of physics is to provide a mathematical framework that underpins our understanding of the world. In the simplest cases, this provides descriptions of processes that are amenable to analytic (mathematical) investigation. The problem is that, for any real world, multi-component problem, this becomes very too complex very too fast. One way of dealing with this is to perform our calculations on a computer - numerical simulation of the problem which offers a faster solution and higher accuracy than calculation. This has been the traditional approach to quantum mechanics, high-energy physics, nuclear, atomic and condensed matter physics to thermal rate constants, molecular energies in chemistry and plasma physics etc, for the last sixty years.
But there is a different way of doing simulation, not based upon solving the myriad equations of quantum mechanics. This is done by mapping one problem of interest on to another, quantum mechanical system over which we have supreme experimental control. Well-controlled quantum systems can be used to reproduce the behaviour of other, less accessible quantum systems.