waynerad writes "Some physicists are proposing using a quantum computer to simulate quantum systems, which are intractable to simulate on a classical computer. This would be huge big breakthrough for figuring out the chemistry involved in assembling large devices atom-by-atom, it seems to me. If, of course, these quantum computers can actually be built. The preprint is here.
'Simulating reality is hard task. The combined computer power of the planet still couldn't run a full simulation of simple quantum systems. However, quantum computers could efficiently simulate other quantum systems. This, in fact, was the original motivation for Richard Feynman to propose such a device as a quantum computer in the 1980s. A quantum device that runs a perfect virtual reality simulation is just a form of a quantum computer but specific things must be taken into account in the design, different from a quantum computer to factor large numbers or run other applications. The authors propose some designs for quantum simulators and point out that such a tool would be invaluable in studying new material designs, especially for new superconductors and magnets. '"