Scientists are working toward building the next evolution of computers: quantum computers. And recently, a team of researchers in the Netherlands made another step toward that future after they successfully sent quantum data to three locations in a network.
That development could lead to the creation of a quantum internet, an essential part of any future attempt to build quantum computing networks.
Cade Metz, a technology correspondent for The New York Times, wrote about this recent development.
Marketplace’s Kimberly Adams spoke with Metz about quantum computing, what makes the concept different from today’s computers and why this latest development with quantum networks involves “teleportation.”
The following is an edited transcript of their conversation.
Cade Metz: Today’s computers store data in what we call bits. And in each bit, you can store either a one or a zero. With a quantum computer, you have what’s called a qubit — short for quantum bit — is that it can store a combination of one and zero at any given moment. So as you string these qubits together, the possibilities for computation become exponentially more powerful, because each qubit can store both these values at once.
Kimberly Adams: You mentioned in your article that quantum computing also needs a comparable network to support it — a quantum network, if you will. What would that look like?
Metz: Well, in some ways, it looks a lot like our networks of today. But with a quantum network, you want to be able to move quantum data. And that’s a very difficult thing to do. If you have a qubit that stores both those values at the same time, if you look at it, if you try to read the data, you suddenly break the qubit. It becomes an ordinary bit where it’s either a one or a zero. So you need a new type of network that allows you to move that quantum data and keep it in that state without breaking it.
Adams: Right, because if you try to move a qubit through a system that’s only used to dealing with bits, it breaks that qubit into bits.
Metz: Exactly. I mean, it’s just fundamental that you cannot copy data and move it in a quantum computer. So you need a new way of taking that data that’s stored in this unusual way and moving it to a new machine.
Adams: So let’s say we do have a network of quantum computers. The internet that we have now completely changed the way the world operates. What would quantum internet do?
Metz: One thing that we need to underline here is that quantum computing is still a ways off. This isn’t going to change our everyday lives immediately. It’s going to change the way scientists do their work. As they get more powerful, we might expand beyond that, but initially, this is going to be something that is used by companies and academic labs and government labs. But potentially, these systems can really change some important things. Drug discovery is one, right? [It can] help us understand the way the human body works and the ways we can address illness and disease. The quantum computer could potentially break the encryption methods that we use to protect our data. So in the shorter term, it’s best to think about it that way. It’s going to change the way businesses compute, the way government labs and academic labs compute.
Adams: That’s how the internet that we have today started out, it was something that was only used by governments and labs. And now it’s being used for everything from, you know, posting pictures of your breakfast to crimes and spreading [disinformation] and misinformation. What happens when you layer quantum technology and quantum computing on top of that?
Metz: You know, a lot of people think that as we move forward, we will continue to use both types of systems in tandem, right? There certain things that a classical system will be good for and there are other things that a quantum system will be good for. Now, you can look beyond that. But I’m hesitant to do that, despite decades of research into this, we’re still waiting for a quantum computer that can do something that is practical and useful that you cannot do yet with a classical machine.
Adams: Let’s say we take something like risk modeling for climate change. Can you walk me through how differently the experience would go trying to do that modeling with the traditional computing power that we have now and traditional computer networks we have now, compared with a quantum computer and interconnected quantum computers in a network?
Metz: Well, that type of modeling requires, you know, enormous amounts of processing power today. If you really want to model a complex system, you have to take in so much data, and you’re struggling to understand how all that data relates to everything else in that collection. A quantum computer, think about it as as finding shortcuts that allow you to better understand the connections between all that data. That’s the hope is that we can find an easier and more straightforward way to understand the connections between all those disparate pieces of data.
Adams: Talking about this almost feels like we’re entering the realm of science fiction. You mentioned things like quantum teleportation. What is that?
Metz: What you can do with two quantum systems that are at a distance is you can, as scientists say, entangle them. Even if they’re far apart, they can be entangled so that when the state of one changes, the state of the other will change. That strange phenomenon can be used to move data. A team in the Netherlands recently demonstrated that you can do this, not just across two distance systems, but across three. And that was an important step because it showed that we can potentially do this for many network nodes and move towards that type of quantum internet.
Adams: I think about how there’s so much technology that we use every day that we don’t understand. How important do you think it is that people understand quantum computing by the time we actually have it showing up in our lives?
Metz: I think we’re experiencing this now with another technology, driverless cars. I do feel like the general public for years did not understand this technology at all, what it was capable of and what it wasn’t capable of. And that can be a dangerous thing. This is something that is approaching our public roads. In a lot of ways, it’s already there under test. You need to understand what that technology can and cannot do, when that’s the case. And it’s good to lay the groundwork and understand what’s coming and understand how that might change our personal lives and the larger way the world operates
Metz’s article, as well as this explainer from Wired, provide good background on the concept of quantum computing and quantum mechanics.
If you want to learn more about quantum teleportation, check out this short video from The Verge’s YouTube channel, Seeker.
Last month, President Joe Biden announced two presidential directives related to all this. One was to enhance the National Quantum Initiative Advisory Committee and put it directly under White House control to feed lawmakers and the public information about the latest developments in the field.
And another was to address the cybersecurity risks. Specifically, the directive calls for the National Institute of Standards and Technology to develop new, quantum-resistant cryptographic standards.
By the way, those directives were released quite appropriately on … May the Fourth. You know, “Star Wars” Day.