QuantAlgo: Quantum algorithms and applications

During the 20th century, the development of information technologies had a huge impact not only on science but also on society as a whole. This unprecedented revolution revealed a need to improve the speed and efficiency of data processing, as well as to strive for better security and privacy. One ultimate limitation of current information processing models is that they assume a simplified representation of physics, relying on classical mechanics. Quantum information technologies promise to break this barrier by achieving the highest security and efficiency allowed by the laws of physics, hence leading to a new revolution in information technologies, in the form of a large-scale network of classical and quantum computing devices able to communicate and process massive amounts of data both efficiently and securely using quantum resources. Despite steady experimental progress, we are still far from this longterm vision, not only due to technological limitations but also to the still-narrow range of applications of current quantum algorithms.

The vision of this project is to combine research on the fundamentals of quantum algorithms with the development of new applications targeted at areas of extreme practical importance and timeliness such as big data and machine learning. The project will complement ongoing experimental efforts in quantum technologies by providing new software tools in order to help lead to a revolution in information technologies, harnessing the power of quantum resources to go well beyond today's capabilities, while maintaining a secure digital society.

Quantum mechanics was developed in Europe a century ago by a generation of now-famous physicists such as Planck, Einstein, Bohr, Heisenberg, Schrödinger, etc. From fundamental research, their discoveries led to a revolution by bringing to modern society disruptive technologies such as lasers, transistors and magnetic resonance imaging. Today, research in quantum technologies gives us a glimpse of a second quantum revolution, with applications such as quantum clocks, quantum sensors, quantum communication links and quantum computers. Many countries around the world are investing heavily in research on quantum technologies in an effort to lead the way in this revolution. In the private sector, leading companies such as Google, Microsoft and IBM have also understood the promises of quantum technologies and therefore opened internal research departments in this area.

To place Europe at the forefront of this second quantum revolution, it is crucial to structure its efforts to create an efficient synergy between all involved players, academic and industrial. Our project could play an important role in this regard by providing key quantum software to exploit future quantum technologies to their fullest capacity. Concretely, while Shor's factoring algorithm was an important motivation for research in quantum computation, one cannot deny that a future quantum computer would be of limited use if all it could do is factorize numbers (especially if in the meantime, we move away from RSA encryption and other cryptographic schemes based on the hardness of factoring). While other applications of quantum algorithms have been found, many of them address abstract mathematical problems, and there are still rather few real-life application areas where quantum algorithms are known to substantially outperform the best classical algorithms. Therefore, new ideas are needed to fully realize the potential of a second quantum revolution. Our project proposes to take an important first step in that direction by providing new quantum algorithms with practical commercial or industrial applications (including e.g. mathematical finance and engineering) and testing them on real data. It is reasonable to believe that the field of quantum algorithms is now ripe for such a challenge, due to the recent development of techniques such as the HHL algorithm, able to provide exponential speed-ups for algebraic problems relevant to practical applications.

Together with future quantum hardware, such applications have the potential to bring transformative advances to science, industry and society.