Although IBM has questioned Google’s results, many researchers say they appear to represent a scientific milestone termed quantum supremacy: When a quantum computer gives the first taste of the technology’s potential by doing something beyond any conventional computer, even if on a contrived problem.
The superposition of celebration and sobriety on display at Google’s quantum HQ was fitting. The company’s supremacy experiment is a signal moment in a recent burst of progress in quantum computing. Tech giants, startups, investors, and governments are plowing more money into quantum computing. Nature estimates that private firms working in quantum-related technology raised $400 million in 2017 and 2018, more than double the amount in the previous five years. At the same time, no one quite knows when today’s quantum technology, even Google’s champ Sycamore, will mature into something useful—or profitable.