Science Friday - What’s Next For Quantum Computing In 2025?

Episode Date: February 5, 2025

It seems that every few months, there’s an exciting breakthrough in quantum computing, a kind of computing that takes advantage of quantum physics to perform calculations exponentially faster than our most advanced supercomputers. Last December, Google announced that its quantum computer solved a math problem in five minutes—a problem that would’ve taken a normal supercomputer longer than the age of the universe to solve. And earlier this month, Microsoft, coming off a quantum advance in the fall, told businesses to get “quantum-ready” for 2025, saying that “we are right on the cusp of seeing quantum computers solve meaningful problems.”So, are we on the cusp? Flora Lichtman is joined by Dr. Shohini Ghose, a quantum physicist and professor at Wilfrid Laurier University in Waterloo, Canada and CTO of the Quantum Algorithms Institute, for a quantum computing check-in and a look at when this futuristic technology could start to have an impact on our lives. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Flor Lichten. Today in the podcast, decoding a technology that keeps getting hyped. There are definitely many areas where quantum can benefit. But it's not that it's going to replace everything that we do with our regular computers. Quantum computing. We keep seeing these exciting new headlines about breakthroughs, like just in the last few months. Google announced that its quantum computer solved a math problem in five minutes that would have taken a normal supercomputer longer than the age of the universe to solve.

Microsoft told businesses to buckle up because we're on the cusp of seeing quantum computers solve meaningful problems. So are we on the cusp? Up next, we're doing a quantum computer check-in. What advancements are at the top of the queue? Which can we throw in the queue in? Here to parse the news is Dr. Shohenegos, a quantum physicist and professor of physics and computer Science at Wilfred Laurier University in Waterloo, Canada, and CTO of the Quantum Algorithms Institute. Dr. Gosh, welcome to Science Friday. Thank you. Glad to be here.

Okay. Before we get to the recent news, can you give us a refresher on what quantum computing is in a way that will not break my brain? I'll do my best. So quantum computing is a very interesting and revolutionary approach to doing computers. So I think we're all familiar by now with regular computers, which are actually quite simple machines. Essentially, they're just a bunch of switches turning on and off inside. If you look at your circuit board, all of those circuits are really just ways to convert all of our

information that we're inputting into a sequence of zeros and ones, binary digits or bits. So in that sense, it's a very, very simple machine. And we're kind of lucky that everything can be converted into just. some sequence of zeros and ones. Turns out that quantum computing is a broader paradigm for computing, where we don't restrict ourselves just to specific values of zeros and ones, but we operate in this very strange new landscape where we allow for some possibility that the quantum bit or qubit is in a state of zero

or some possibility that it's in a one. And so it's kind of like exploring a much larger landscape of all these in-better, between combination of possibilities of zeros and ones, like 80% zero, 20% one, which all may sound like it's, you know, getting confusing and there's a lot of uncertainty in it. Right. This is where the brain breaking begins. Exactly. So don't worry, this is actually quite counterintuitive compared to what we normally do. Think about computing, which is what makes it, on one hand, confusing. On the other hand, powerful. So really what has happened and recent years is this shifting of how we approach this idea of uncertainty and, you know, looking

at that entire spectrum of possibilities between zero and one. And if you're very clever, we can build these pathways through this computational landscape to reach the answer faster based on being able to control these possibilities, what we call superpositions of zeros and ones. So in a way, you might think of it like having this probability wave that flows through your problem landscape, and if you can control the wave, you get to your answer actually faster. Sometimes flowing to your answer is actually faster than jumping discreetly using zeros and ones. So maybe that helps to try to visualize this very peculiar new framework. Yes, yes, definitely.

I mean, and is the result that a computer can do sort of multiple calculations at ones? If a bit can be more than just a zero or a one, if it's more than the binary, Does that mean it can sort of explore different pathways at the same time? Yeah, but I want to be careful there. I know that often quantum computing is described as exploring all possible values all at the same time. Yes, in a sense, that's true because, of course, when we say superposition, it's that idea of more than one possibility at the same time. However, when we get to the final answer, the trick is that you can only eventually get

to the one solution, right, which is some particular specific string of zeros and ones, which is your final answer. It's not enough just to calculate everything and all possibilities at once because the final answer then could be any one of those possibilities. So the key is that, yes, you explore all these possibilities, but you have to explore them cleverly, not just leave it at, oh, you can do it all at once. Because if you do it all at once, then you might get any one of those possibilities. And there are many more wrong outcomes than there are correct ones. So there's more to the game. What do quantum computers look like? What should what what should I picture when we're talking about them? Well, I think if you

Google quantum computers, the one image that comes up a lot you'll see is a very amazing sort of very different kind of image. It doesn't look like a computer. It looks more like this golden chandelier. And that is a particular type of quantum computer that's being built by companies like IBM and Google and others around the world. But most of what you're actually seeing in the image is all of the control and the electronics and the cooling systems you need to operate the processor. The processor itself is actually quite small. It's a small little chip that is very hard to see. So that's one image of a quantum computer. There are others, but none of them look like our current laptops. Let's check in on some of these recent advances. So in December,

Google announced that its quantum computer solved this problem that would take existing supercomputers, you know, longer than the age of the universe to solve, which sounds very cool. Is it cool? It is definitely cool. But there's always a bit of a butt. It's cool in the sense that as a researcher myself, it's exciting because this is a standard benchmark math problem that is used to try to understand the performance of quantum. computers. So in that benchmarking test, Google did show that they were able to solve the problem very fast. And the reason this benchmark is used, this particular math problem, because it is actually very hard, even for supercomputers to solve the problem. And it's really, it's not really

a solving of a problem. This benchmark problem is actually a way to try to sample random numbers. And turns out that's quite difficult for supercomputers to do. Whereas, Google was able to complete that task quite fast, but it is, in fact, a made-up math problem. It's not like solving that problem actually leads to any particular useful real-world application, like, you know, maybe helping to design better molecules for chemistry, materials design, for example, or, you know, some kind of a health care, drug development things. So that level of real-world application is not there yet. So on one hand, it is exciting, but on the other hand, it's not real world.

Okay, it's not real world. Were there any other pieces to that advance that signaled we are in a new phase of quantum computing? Yeah. One other very exciting aspect of that announcement was that Google was able to address this question that comes up a lot and it's one of the biggest challenges for quantum computing development. and that is a question of errors. So quantum computers actually are very, very difficult to control precisely because even the smallest disturbance will throw it off and there'll be errors in the computation. It's kind of like our regular computers. You know, these days we don't see it much,

but there used to be those overheating problems and computers sometimes frees up even today. Yes, the fan goes on and you're just, and then nothing works anymore. Yes. Exactly. So with quantum computers, computers, a problem is infinitely worse. For example, Google's machine and IBM's machine, these computers have to be cooled down to temperatures that are colder than outer space. So even the tiniest amount of heating causes errors. And it's not just a heat question. Anything that interacts with this quantum processor will throw it off. So they're very, very fragile. What Google did, that's exciting, is that they used,

this framework that we call quantum error correction, where you can actually take each of these individual quantum bits or qubits, and by coupling all these cubits together, you can, in a sense, reduce the error as you add more and more cubits. Normally you would think that the errors would go up because there's even more cubits, they're all going to have errors and that will multiply. But there's this clever framework where you can actually reduce error correction as long as each of the cubits has a particular threshold of error and failure. So what Google was able to show is that as you increase the number of cubits, you can actually reduce the error.

And obviously, that's a very important piece of being able to scale up and build large-scale quantum computers. So that was very exciting. Why are companies like Google and Microsoft and IBM working on quantum computing? I mean, is this akin to sort of like the race to develop AI where these companies want to own the market because quantum computing could be applied to a million bazillion things and we can't even dream up the applications yet. Is that the right analogy or is there something else going on? Well, yeah, in the end, quantum computers can unlock huge performance advantages in certain types of

areas. So one of the key applications, which kind of kick-started this whole field, was to solve this one math problem, which sounds kind of like a fairly simple problem. And that's a very simple problem. factoring, meaning if I take a number like 15 and ask, can you find the factors, well, that's easy. That's three times five. But if you go to numbers that are, let's say, you know, 100 or 200 digits long, even our supercomputers have a hard time cracking that problem. And this is an important problem because hard math is actually what keeps all of our information safe because it's at the foundation of encryption systems. So for example, if a hacker wants to hack your passwords, actually that encryption is based on factoring. So the hacker would have

to know how to factor large numbers. And turns out that's computationally hard, and that's what keeps our information safe. Turns out quantum computers can actually solve a problem like factoring exponentially fast. So this is actually what got everybody to wake up and say, oh my gosh, if you can build that kind of large-scale quantum computer, you actually can basically read everybody, these secrets and hack into passwords and you know, find out about people's finances and healthcare records and things like this. So that's one of these big, big applications and that has led to this race around the world to try to be the first to get there. But that's only one. There's other possible applications, as I was saying, in developing drugs and, you know,

doing the simulations you need to understand molecules and quantum chemistry. There's also applications in being able to solve optimization problems. such as trying to get the best sort of supply chain, right? That's an example of an optimization problem that we see all the time around the world. So there are definitely many areas where quantum can benefit. But it's not that it's going to replace everything that we do with our regular computer. After the break, why governments are pouring billions of dollars into developing this technology. It can be weaponized, this technology.

So in that sense, absolutely, there's a lot of similarities with an arms. race. Stick around. I know the U.S. and China are both spending billions on quantum research. What do you make of this? Well, you're right that there's definitely a lot of funding. And in fact, there's more than U.S. and China, I'd say as of the last count, there's been over 30 different governments in the world that have announced national quantum strategies. And I think the reason there is because it's recognized as something that is very critical to the security of countries. So it is related to sovereignty and security of data. Do you see this as a type of arms race?

I think, yes, it is very similar to what we've seen historically with arms races, because it can be used. Absolutely, it can be weaponized, this technology. Governments are racing to build out plans because it's not just about having the technology to deploy, but also to be able to defend against the technology being deployed against their own citizens. So in that sense, absolutely, there's a lot of similarities with an arms race. You know, we've been talking about encryption and state security.

Do you see quantum computers changing my life, changing our listeners' lives in meaningful ways? Yeah. So quantum is not really a technology that's going to replace our current computers. Because honestly, our laptops are just fine for almost everything that we, do on an everyday level. It's not like I wake up every day and need to solve a complicated molecule problem. So if I'm doing email, my laptop is just fine. But even with email, what will be impacted going forward is that on the back end, every time we send email, we are sending

encrypted data. So the encryption on the back end will start to change and we will be shifting over to what we call post-quantum encryption, which is a way to try to protect against future hacking by quantum computers. And eventually we'll be sending data through what we call quantum networks, where our information is actually being encoded using quantum information built into qubits. And just like we don't see the encryption running on our current computers, we probably won't see it going forward on our laptops and devices. but it will be there. So it will be impacting us. We just perhaps will not see it every day.

Are people using quantum computers outside of the lab? Are they outside of the demo space at this point? For the most part, they're still in development. However, there are certain areas in which there is already what we call real world, ready to use kind of potential applications, that there are companies that are accessing this. So, for example, there's a company called D-Wave, which offers a quantum device that is actually very much tailored to do one type of problem, and that is optimization kinds of problems. Everything is an optimization problem at some level. So like I was mentioning earlier, if, for example, you wanted to find the best routing system for your delivery trucks, they have a very, very complicated algorithm that they need to run to be able to, deliver all of your packages and you know how we get really annoyed when it doesn't come within the next day. It's actually quite a hard logistical problem. So in the back end, there's always some kind of an algorithm running to try to optimize how all those deliveries work. And that's

one example of optimization. So there are companies that have used that tool to actually improve their optimization calculations. So it's happening. It's just not a universal quantum computer. It's specifically for optimization, but it's definitely real world already. How do you see quantum computing playing with AI and machine learning? That's a great question. I think the future is really going to be in this hybrid space where both quantum and AI will be applied to whatever is the computational task, where some parts of the task will be done using the quantum processor, some parts will be done using machine learning, so that the combination will

provide you with the optimal performance. I want to come back to where we started. Do you think we're on the cusp of something big with quantum computing? You know, it's always very hard to predict the future of any technology. I think we've always got it wrong. But given that, disclaimer, I will say as a scientist, yes, I am quite excited in all of the progress that has been made. And I'd say that it's faster than I would have predicted. And I think the big exciting moment will happen when when somebody announces, yes, we have solved an actual real world problem. Maybe it's in healthcare, maybe it'll be in finance. My guess is it's going to be in some kind of quantum chemistry problem,

which might be applied to material design or biology. And that's, I think, coming. It's in the next few years. I think we're going to see some very exciting announcements. I really appreciate you walking us through this today. Thank you. Thank you. Dr. Shahini Ghosh, a quantum physicist and professor of physics and computer science

at Wilfred Laurier University in Waterloo, Canada, and CTO of the Quantum Algorithms Institute. And that is about all we have time for. Lots of folks helped make the show happen, including... Praise Aguchi. Sandy Roberts. Robin Kasmur. Jordan Smudjik.

I'm Flora Lichtman. Thanks for listening.