Google claims it has achieved 'quantum supremacy' – but IBM disagrees

For Google it was a historic announcement: a declaration that it had won the race to achieve "quantum supremacy" – the moment that a futuristic quantum computer performed a task that stumped even the most powerful standard computer in the world. But for all the fanfare, which saw Google's CEO Sundar Pichai compare the feat to building the first rocket to reach space, the claim has sparked a bunfight. The tech firm's rival, IBM, was swift to dismiss the excitement. Google has not, it asserts, achieved the highly prized goal of quantum supremacy. Google published its claim in the journal Nature on Wednesday after an earlier report on the work appeared briefly on a Nasa website last month. The paper describes how a team led by John Martinis, leader of the research team working on quantum supremacy, built a superconducting quantum processor named Sycamore that harnesses the weirdness of quantum physics to crunch through thorny problems.