HOLD ON A QUBIT
While the peer-reviewed research has drawn plaudits, with MIT's William D. Oliver comparing its findings in Nature to the Wright brothers' first flights, sceptics say Google is over-selling its achievement.
Researchers at IBM, Google's main quantum computing rival, said a supercomputer with additional disk storage can solve the random number problem in at most 2-1/2 days, with greater fidelity - or accuracy.
They also said Google risked misleading the public by implying the new-style computers would replace existing ones.
"Quantum computers will never reign 'supreme' over classical computers, but will rather work in concert with them, since each have their unique strengths," Dario Gil, director of research at IBM, wrote in a blog.
