Although recent findings have poured cold water on quantum computing hype, don’t count the technology out yet. On 4 March, Google and XPrize announced a US $5 million prize to anyone who comes up with use cases for quantum computers. If that sounds like an admission that use cases don’t already exist, it isn’t, says Ryan Babbush, head of quantum algorithms at Google. “We do know of some applications that these devices would be quite impactful for,” he says.“A quantum computer is a special purpos...