Each of these combinations, they add up like waves in a pool of water. The combinations that are wrong, they cancel each other out. And the combinations that are right, they reinforce and amplify each other. So at the end of the quantum computing program, all that’s left is the correct answer, that we can then observe here in this universe.
Now, if that doesn’t make complete sense to you, don’t stress. You’re in good company.
Niels Bohr, one of the pioneers of this field, he once said that anyone who could contemplate quantum mechanics without being profoundly shocked, they haven’t understood it.
But you get an idea of what we’re up against, and why it’s now up to us cryptographers to really step it up. And we have to do it fast, because quantum computers, they already exist in labs all over the world.
Fortunately, at this minute, they only exist at a relatively small scale, still too small to break our much larger cryptographic keys. But we might not be safe for long.
Some folks believe that secret government agencies have already built a big enough one, and they just haven’t told anyone yet. Some pundits say they’re more like 10 years off. Some people say it’s more like 30. You might think that if quantum computers are 10 years away, surely that’s enough time for us cryptographers to figure it out and to secure the internet in time.
But unfortunately, it’s not that easy. Even if we ignore the many years that it takes to standardize and deploy and then roll out new encryption technology, in some ways we may already be too late.
Smart digital criminals and government agencies may already be storing our most sensitive encrypted data in anticipation for the quantum future ahead. The messages of foreign leaders, of war generals or of individuals who question power, they’re encrypted for now.
But as soon as the day comes that someone gets their hands on a quantum computer, they can retroactively break anything from the past. In certain government and financial sectors or in military organizations, sensitive data has got to remain classified for 25 years. So if a quantum computer really will exist in 10 years, then these guys are already 15 years too late to quantum-proof their encryption.
So while many scientists around the world are racing to try to build a quantum computer, us cryptographers are urgently looking to reinvent encryption to protect us long before that day comes.
We’re looking for new, hard mathematical problems. We’re looking for problems that, just like factorization, can be used on our smartphones and on our laptops today. But unlike factorization, we need these problems to be so hard that they’re even unbreakable with a quantum computer.
In recent years, we’ve been digging around a much wider realm of mathematics to look for such problems. We’ve been looking at numbers and objects that are far more exotic and far more abstract than the ones that you and I are used to, like the ones on our calculators.
And we believe we’ve found some geometric problems that just might do the trick. Now, unlike those two- and three-dimensional geometric problems that we used to have to try to solve with pen and graph paper in high school, most of these problems are defined in well over 500 dimensions. So not only are they a little hard to depict and solve on graph paper, but we believe they’re even out of the reach of a quantum computer.
So though it’s early days, it’s here that we are putting our hope as we try to secure our digital world moving into its quantum future. Just like all of the other scientists, we cryptographers are tremendously excited at the potential of living in a world alongside quantum computers. They could be such a force for good.
But no matter what technological future we live in, our secrets will always be a part of our humanity. And that is worth protecting.
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