We should avoid quantum computing hype – but that doesn’t mean that we should overlook its profound potential

Ironically, conversations about quantum computing tend to be conducted in one of two states. They are either carried out in frenzied excitement or include weary debunking. Sometimes they flicker between the two. The radical promise of quantum computing is real, but the caution is a perfect antidote to the hype – and we would do best to bear both in mind.

That means there is also an edge of caution to announcements like this week’s, that Google says it has achieved “quantum supremacy” and developed a quantum computer able to do things a classical computer cannot. There are plenty of reasons to be cautious. There’s a worrying amount of cash riding on these breakthroughs, which are jazzed up in press releases and marketing in a way that traditional research organisations normally avoid; everyone wants to be first to make these claims; they are difficult to understand and even harder to actually test, meaning that people can make exaggerated claims more easily.

But there are so many reasons to be excited, too. Quantum computing is a truly new field in which we are seeing genuine innovation, so unprecedented that it threatens to turn entire paradigms on their head. That’s why it is important to stay excited about this week’s news, which even the usually put-upon academics in quantum computing and mechanics greeted positively. Quantum supremacy might only be a milestone, one that doesn’t have much practical application or specific meaning, but it is a milestone on a journey that could fundamentally reshape the world.

It might allow us to build entirely new kinds of materials and batteries that alter how we store energy. But it might undermine the cryptography that keeps information in computers safe. And it might do so even sooner than we think, with advances and breakthroughs coming at a fairly fast clip. Or it might take decades, with quantum computers seeing little immediate application.

Staying overly cautious or getting carried away by the hype both dull the profound effect that quantum computing will have, and could mean we miss some of the most radical technology in the world. Much better to stay both sceptical and thrilled.