Quantum physics already upended our lives over 60 years ago with the invention of the laser and the transistor. Today, with a second quantum revolution in sight, the science promises a radically different future from the world we know today.
Marko Erman, Chief Scientific Officer at Thales, offers us a preview of life in a quantum world.
How do you see the post-Covid world that everyone's talking about?
It would be premature and a little presumptuous of me to try to describe what the world will be like once this unprecedented public health, economic and social crisis is over. But I do have some thoughts on the subject. For example, I think the crisis has made a deep impression on society's appreciation of the major challenges that lie ahead, with healthcare, education, the environment and security at the top of the list.
These concerns are very much part of the national and European stimulus plans being put in place to pull our economies out of the crisis. In France, for example, the government announced the fourth Investments for the Future programme (PIA 4) at the start of this year. And the priorities of this plan include digital technologies, of course, but also medical research, healthcare, cities of the future, climate change and digital education — not to mention green innovation and technologies, which account for fully one-third of this latest PIA programme.
We have seen how digital technologies have made society more resilient to a pandemic and how they help to deal with the consequences for public health, the economy and society at large. Whether we've been working from home or doing more online, remote transactions have literally exploded.
And cybercrime has exploded too…
Which just goes to show the importance of cybersecurity if we want to reap the benefits of digital without living in fear of the dangers involved. It also speaks to the need to find new ways of protecting our societies from these new risks and dangers and to explore disruptive new technologies that will help us overcome the major challenges I mentioned earlier.
One of these disruptive technologies is quantum physics, which is attracting a lot of attention at the moment…
That's right. Using the quantum properties of materials opens up countless new opportunities in areas as varied as manufacturing, mobility, defence, healthcare and the environment. There is virtually no limit to people's creativity when it comes to imagining new applications of quantum technologies.
More specifically, which markets will be affected by this new quantum revolution in the short to medium term?
This second quantum revolution will mainly affect sensors, communications and computers. Quantum computers will be capable of solving problems of process optimisation and simulation that any conventional computer, current or future, would take thousands or millions of years to achieve.
One of the markets that will be disrupted relatively quickly will be healthcare. Messenger RNA vaccines have demonstrated the power of deep tech in enabling scientists to work at cellular or molecular level. And this is just the beginning — cancer treatment, and the treatment of many other diseases, could be profoundly transformed by quantum technology. But before that, the molecular and cellular world needs to be observed, understood and modelled. Quantum computers will be able to construct models of complex molecules made up of thousands of atoms, like proteins and other living matter. And to do that, we are going to need new, precisely "targeted" processing techniques.
In addition, quantum sensors could lead to new medical imaging techniques, like the MRI imaging we know today but sufficiently targeted to provide information on a cellular and molecular scale.
The RF detection performance of quantum sensors could also open up exciting new possibilities in neuroscience, allowing us to observe the brain in real time and with a spatial resolution well beyond today's capabilities. With degenerative diseases destroying the lives of a growing number of people, it is more important than ever to understand exactly how the brain works and ensure early detection of anomalies, lesions and cognitive disorders, but also to precisely measure the effects of treatments and how they act. Quantum sensors could play a significant role in meeting this major challenge.
You also mentioned the environment. How can quantum physics help address climate disruption?
Every technology has both a direct and an indirect impact on the carbon footprint of human activity. The direct impact of a technology may be to increase this carbon footprint by consuming electricity, while the indirect impact may reduce the footprint by making a system more energy efficient. To decide whether a technology is beneficial for the environment, you need to look at both the upsides and the downsides.
In most cases, a quantum system consumes much less electricity than an equivalent system based on conventional technology.
A quantum computer, for example, will need a very cold cryostat (close to absolute zero) for a unit measuring a few cubic metres, but its electricity consumption will be measured in kilowatt hours. No conventional supercomputer will ever have the same computing power, and the electricity consumption of today's high-performance computers is measured in megawatt hours because they need so many processors — several thousand in some cases.
As for quantum sensors, they will be highly miniaturised, but in the case of RF sensors, they will also be extremely wideband. Covering the same spectrum of wavelengths with conventional technology would take large numbers of sensors, some of which are thousands of times bigger than their quantum equivalents. So in this case too, quantum technologies are the clear winners when it comes to energy usage.
And when you look at indirect impacts, quantum technologies come out on top again.
By optimising the systems used in air traffic management, energy distribution, waste collection and processing, natural resource management, etc., quantum computers will reduce their carbon footprint. Today's computers cannot solve most of these optimisation issues when more than a few variables are involved.
Quantum computers could also be used to design new materials with properties optimised for thermal insulation, for example, or to design parts that are significantly lighter than today's but have the same mechanical performance.
Sensors like quantum gravimeters1 will offer order-of-magnitude increases in sensitivity compared with existing instruments, making it possible to observe the Earth with extremely high granularity and understand the changes taking place.
As well as quantum computing and quantum sensors, you mentioned quantum communications…
Quantum technologies are going to take communications security to a whole new level. A quantum key (i.e. a series of qubits2 whose quantum states constitute the code) cannot be broken because of the inviolability of the laws of quantum mechanics: when the key is read (decoded) it is destroyed, so any intrusion is noticed immediately.
The principles behind quantum communications were demonstrated more than a decade ago. But that was for point-to-point communications and the distances were limited because of absorption by the optical fibres. Boosting the signal with conventional optical repeaters (or amplifiers) would have disturbed its quantum nature, destroying the code. In practical terms, that meant information could only be sent over a distance of about 50-150 km.
Today, efforts are underway to demonstrate the feasibility of quantum networks as big as a continent like Europe. To overcome the limitations of photons being absorbed by the optical fibre, the idea is to distribute the quantum keys via satellite to metropolitan quantum networks with enough suitable fibres in place to connect large numbers of users in a radius of more than 100 km.
In Europe, work on this type of communications network is being conducted by various consortia, with Thales and Thales Alenia Space as major members and support from ESA, Horizon Europe and the Member States.
In the quest for ultra-secure communications networks — and with the growing dangers of cybercrime making that goal increasingly important — quantum cryptography is one avenue that needs to be fully explored in order to protect the vital information of governments, institutions, businesses and individuals.
Is it a matter of sovereignty?
Absolutely. That's why the United States and China are competing so fiercely to master these technologies.
What about Europe?
Europe has world-class scientific, academic and industrial capabilities in this field and can play its hand well if it decides that quantum cryptography is a strategic priority and makes the necessary investments. I have high hopes that the Covid crisis will also have served to raise awareness of quantum physics as one important way to build a future we can all trust.
1 Gravimeter: instrument used to measure gravitational acceleration
2 In the binary logic of conventional computers, information is coded as 0s and 1s (bits). In the quantum world, the basic unit of information is a qubit, which can be 0 and 1 at the same time.