For those reading, could you explain your role at the Quantum Nanoscience Laboratory and tell us a little bit about your current research?

I’m the director of the Quantum Nanoscience Lab in Sydney. In my role there, I oversee a research program that is broadly exploring many of the questions related to quantum physics and quantum science and its application in new technologies. My current research is focused on creating devices at the nano-scale. These are tiny electronic systems that allow for the manipulation of light and matter – specifically single-electrons to process information, to create new computing technologies, new sensing opportunities and embedding quantum mechanics in electronic devices for a whole suite of new technologies.

What are some odd quantum effects you’ve experienced through your experiments nearing temperatures of absolute zero?

At temperatures that approach absolute zero, the world is vastly different to our experience in the everyday life that we lead. Down there at those temperatures, the thermal motion of matter, of atoms, slows down and almost stops. You can think of absolute zero as defining the temperature scale whereby the thermal jostling and vibrational motion that we experience ceases. If you put your hand on something that’s hot, you’re feeling the vibration of the atoms there, the vibration of the solid. Absolute zero is the temperature where those vibrations cease. Getting very close to that is important because we’re trying to study quantum physics, it’s a collection of phenomena that is very weak, very fragile, and you would disturb the system by having it at a higher temperature and all those vibrational modes lead to a kind of blurring of the physics. Getting down the temperature is necessary to see the odd quantum effects. The kind we see is quantum superposition or having objects in multiple places at the same time. Effects related to quantum entanglement where there is some connection or correlation between quantum objects like single electrons even if they’re separated by large distances. It could be distances on the other side of the city or the galaxy. For us, it’s only a distance on the other side of a computer chip but none the less quantum entanglement is a powerful resource for technologies. Pretty hard stuff, pretty hard-to-understand ideas, but necessary to get to the temperatures that we do now, at millikelvin (mK), a few millikelvin, that is one thousandth of a degree above absolute zero that we get to, to study these effects.

What do you theorise happens at an absolute zero temperature?

Well, we can’t reach that temperature scale. It turns out that there are many aspects to it, but it’s like the speed of light. Objects that have mass can’t reach the speed of light, you’d need more and more energy to accelerate them just that little bit more. They approach the speed of light but it becomes more and more challenging to get there. Absolute zero is similar. If you imagine a refrigerator cooling an object, as you get colder and closer to absolute zero, it becomes harder to get that last bit of heat out. It asymptotes or approaches absolute zero but never quite gets reaches it. Quantum fluctuations happens at those temperatures. Something strange where nature can allow for…well, it’s kind of like you can borrow money from the bank and pay it back so fast that nobody notices. In nature, that is possible. Quantum mechanics allows you to create particles out of nothing, so long as their lifetime is such that they’re short relative to their energy. This is a form of the quantum uncertainty principle; we call it quantum fluctuations - violations of the conservation of energy - that can happen on very short timescales. It leads to a fluctuating environment, like the kind of fluctuations you get from increasing the temperature of an object. If you were to reach absolute zero, you would still have quantum fluctuations and the world would have objects popping in and out of existence on a very fast timescale.

What are some real-world applications or implications of achieving absolute zero?

It is the regime we must work in now, to be able to access those strange, odd quantum effects. We’re interested in using those quantum effects to build technologies. We must reach that extremely cold regime. You might think, “What kind of a technology is it going to be? It doesn’t sound like it’s very widespread if you have to get to absolute zero, I can’t imagine carrying around in my pocket a device that’s operating at absolute zero.” If you think for a moment about the device that is in your pocket, your phone, when you use that to access online services or use it to call an Uber or search a database or find something online, your hand-held device is just uploading that information to a large computer that is in the cloud. The crunching and the computational heavy-lifting happens in the cloud and the information is exchanged. The kind of hand-held it is doesn’t matter where that cloud computing solution is. It could be in a warehouse and that warehouse might have special refrigerators. Most data centres have special environments for their computers. If they were computers where their chips were cooled to absolute zero but you could access it online, I don’t think that would be too much of a constraint if you were to access it in the way that you access online services today.

Where do you see your research headed 20 years from now and going forward how do you see quantum technologies impacting society?

I think that we are on the brink of a real switch in the way in which quantum physics and the bizarre aspects of quantum physics are used for technological purposes. It does feel a little bit like similar technological revolutions that have happened in the past when it was possible to mathematically describe the physics of electromagnetism very quickly, we had radio, television, and the internet and so on. Once we understand the basic physics, then we end up with technologies that just impact every area of society. Imagine the world without transistor and integrated circuits and computers. It’s impacted our entire civilisation, our entire society from medicine and disease to how we trade, to how we conduct all our business. You can trace that back to some very fundamental physics. In fact our entire economy is resting on some very fundamental physics that were uncovered in the last 100 years. The next 20 years I think are going to be about this new world that opens up because we have been able to harness the power of quantum physics, exploiting some of these really strange effects to do things technologically that we just don’t have any means of touching right now with the existing laws of physics that we have access to.

Dishonored 2’s Reach and Blink abilities granted by The Outsider allow them to teleport from one position to another. Is there current research focused on quantum teleportation on a molecular level, or is it a pipedream we should give up hope for now?

We should never give up hope. It’s often the case that science fiction and our creative side of who we are as a culture that leads the way. What you see in Dishonored 2 is science-fiction, but imagining what kind of powers we might want…it’s now over to the scientists and the engineers to follow that lead and say, “Okay, how do we actually create such a technology. Is it possible? What do we need?” Where we stand today in terms of teleportation is it’s not total nonsense. It’s not a pipedream. We can teleport the quantum state of atoms and photons of light of electron states. That’s not the quite the kind of teleportation when you think of Star Trek or what’s happening in Dishonored 2, but there is some basis in reality, the idea that I could recreate the entire quantum state of an object at some distance. What we’re not transporting in quantum teleportation is the matter itself. It’s more like we’re transporting the recipe as to how to make it. Just like if you had in your pantry all the necessary ingredients to make a cake but you would need to know exactly how to assemble those ingredients into the food you were trying to produce. We can do that now at the quantum level. Recreate the exact state of a quantum system by teleporting it across long distances. How we go over the next few decades to seeing that allow for the kind of teleportation you see in the game. That’s an open frontier of research.

Another key power in Dishonored is Bend Time. The ability to manipulate time is a massively desirable power. We know that time dilation has been observed when comparing clocks on airplanes and space shuttles, but is there any ground-level research happening around time dilation and is it something that could realistically be harnessed?

Yeah it is something that is harnessed today. If you’ve used Google Maps on your phone or anything like that, that is based on the global positioning system (GPS). You’re making use of those aspects of general relatively or special relatively that came from Einstein that involved time dilation. If you were to use GPS without accounting for the time dilation, given that you’re communicating with satellites and those satellites are moving at very high speeds, if you don’t account for it, then you end up being out of your location by hundreds of meters. It’s quite a large effect. Your Uber driver is not going to find you without accounting for the time dilation in comparing your clocks and those in satellites. It’s an aspect of our world that is not science fiction. Time dilation is something that falls out very naturally from Einstein’s understanding and framework of general relativity and something that we’re still grappling with. I can say those equations, the same equations that were used for GPS, those also allow for mathematical solutions that are very strange space-time objects. There are solutions that involve loops and solutions that have causality in a cycle so that the future is affected by the past in the usual way, but space-time wraps around and creates some kind of Groundhog Day scenario where the future dictates the past and the past dictates the future, and you’re stuck in a loop. That seems bizarre, but it is a solution for those equations that we’re using for GPS. We sort of neglect those solutions and say, “That’s the non-physical bit. Forget about that.” It’s the square-root of a negative number or something. Only later we realised that those mathematical solutions that we discard often do have some basis in reality for describing something else yet to be discovered. I don’t know. Is it something that could realistically be harnessed? We would need access to new physics. At the moment, the physics that we have don’t allow for time travel in the way that we would love to have it at our discretion. We also know that the physics are incomplete and there are many open areas that are in this field that may have impact on such powers that you see in the game.

As the authority on the matter, what is one video game that more or less nailed its representation of quantum mechanics and how?

I really have to say that Dishonored 2 is the first time I’ve seen some of these ideas really done in a way that does them some justice. I have no idea whether the creators of the game intended it that way, but given my day job as a quantum physicist, when I play the game it certainly reminds me of quantum-inspired ideas. It’s not over the top. It’s not like you can flick a switch and dial back time for the entire universe and just travel back in time and when I do that everyone experiences that earlier time. That is often what you see portrayed in movies. Here it’s very different. It’s limited, it’s constrained, it’s subtle use of technology that then give us access to those kinds of powers. Dishonored 2 is an example of a game that really got it right in that sense. I’m struggling to think of anything that’s done a better job.

What’s the most inaccurate portrayal of quantum theory you’ve ever had to sit through in a video game?

I don’t know about in a video game, but I can tell you that there was a movie called What in the Bleep Do We Know? that came out in about 2005. That was something else. It was some kind of quasi-religious political mumbo-jumbo for some purpose. It was quite far from what one thinks about in terms of realistic physics. Hollywood is getting better. What we see here in Dishonored 2 is an entirely new medium in which to experience some of these ideas. As I said before, I don’t think that the creators of the game necessarily intended this to be a show of the powers and ideas of quantum physics. I think they had many other different things in mind. From my perspective when I play that game, it feels grounded in a reality that kind of takes us from where we are today, takes us along a path where there are open questions in the field of quantum mechanics, in the field of gravity and relativity, and then imagines what might be possible decades into the future, that we could harness those types of technologies. It’s grounded in reality but I think it still leaves open many possibilities for the imagination.

What are some misconceptions or tropes on quantum theory that are often peddled in popular culture?

One of them is in quantum computing. There’s a lot of hype around quantum computing. It feels like it’s going to fix everything. Got a problem? Climate change? Fixed - quantum computing. That’s nonsense. There’s a reason it’s nonsense. We have to think about what the world would be like if it was possible to create a computer that could be all powerful and do all things. That sort of implies something very fundamental about the world we live in. It implies that things we thought were hard, they’re not hard for a quantum computer. Well, does that mean there aren’t any hard problems? Does that mean that composing music is as easy as listening to it? That doesn’t make sense. Some things must be harder than others. If you start from that kind of familiar basis, it’s an obvious statement. If you accept that there will be no computational paradigm that will make all problems suddenly easy, then that can’t be true. There must be problems that will always be hard, otherwise the world would be totally absurd if everything would be easy as everything else. It’s a misconception that quantum mechanics gives you god-like powers. It gives you powers in certain areas in certain problems in certain fields, and we do think that’s incredibly powerful. We think it’s certainly going to lead to a revolution in technology. Don’t get carried away to the point that was ever challenging in any way now melts away and becomes trivially easy. It just simply can’t be. It’s an open question in the research field as to which problems can yield to quantum mechanics and which will remain hard problems. It has to be that we still have hard problems despite quantum computing. Anything further to add?