Of all the common retorts in the computer world, the phrase "If only software could catch up with hardware" probably ranks pretty high. Sometimes, however, software does catch up with hardware. In fact, this time around, software seems to be able to go as far as unlocking quantum computing for classical computers. That's according to researchers at the Riken Center for Quantum Computing in Japan, who have published an algorithm that greatly speeds up a specific quantum computing workload. What's more, the workload itself - called the time evolution operator - has applications in condensed matter physics and quantum chemistry, two fields that can unlock new worlds within our own.
Usually, an improved algorithm is not completely out of the ordinary; After all, updates are everywhere. Every application update, software update, or firmware upgrade basically brings in revised code that either fixes the problem or (hopefully) improves performance. The improved algorithm is good, as anyone with an AMD or NVIDIA graphics card can attest. But let's face it: We're used to being disappointed with performance upgrades.
In this case, however, the performance improvement is extraordinary. Really, the results could hardly have been more impressive. With improved algorithms (themselves a hybrid of quantum and classical methods), quantum computers of the future can be simpler than we think: they will be able to tackle bigger problems faster than we expect, and at a lower cost. But the performance gains are not limited to that. They could make it possible for conventional machines to tackle problems of a level of complexity that only quantum computers are said to be able to solve.
"Time evolution operators are huge grids that describe the complex behaviour of quantum materials," explains Kaoru Mizuta of Riken's Centre for Quantum Computing. They're very important because they give quantum computers a very practical application - a better understanding of quantum chemistry and solid state physics."
