Google Thinks it’s Close to “Quantum Supremacy.” Here’s What That Really Means
It’s not the number of qubits; it’s what you do with them that counts
By Martin Giles and Will Knight
Seventy-two may not be a large number, but in quantum computing terms, it’s massive. This week Google unveiled Bristlecone, a new quantum computing chip with 72 quantum bits, or qubits — the fundamental units of computation in a quantum machine. As our qubit counter and timeline show, the previous record holder is a mere 50-qubit processor announced by IBM last year.
John Martinis, who heads Google’s effort, says his team still needs to do more testing, but he thinks it’s “pretty likely” that this year, perhaps even in just a few months, the new chip can achieve “quantum supremacy.” That’s the point at which a quantum computer can do calculations beyond the reach of today’s fastest supercomputers.
When Google or another team finally declares success, expect a flood of headlines about the dawn of a new and exciting era. Quantum computers are supposed to help us discover new pharmaceuticals and create new materials, as well as turning cryptography on its head.
But the reality is more complicated. “You’ll struggle to find any [researcher] who likes the term ‘quantum…
