Quantum technologies, the subject of a report that was to guide the French strategy for investment in this field, are full of promise … They use the surprising properties of matter on the scale of the infinitely small, and promise a revolution in computation and information processing. But there are still obstacles to overcome before we can fully master them. Quantum physics, different from classical physics, is a tool for describing matter on a microscopic scale. It appeared in the early 20th century when we wanted to clarify the true nature of light: was it a wave or a particle?
By taking up the theories of the physicist Max Planck – who had introduced the term “quantum” to denote energy particles – Albert Einstein revolutionized the world by explaining that light was both a wave and a particle. Quantum mechanics is based on this duality, according to which an object can be in several states at the same time. Physicist Erwin Schrödinger imagined a cat locked inside a box with a vial of poison that would be dead and alive at the same time – a complete theoretical experiment illustrating the difficulty of understanding this counterintuitive discipline, with a difficult reputation.
>> Read also – Thales presents an intelligent brain to guide planes
If this “at the same time” can hardly be generalized on the macroscopic level, on a par with the infinitely small, it is indeed a reality. “As soon as we miniaturize things, we are forced to take quantum mechanics into account,” Daniel Hennequin, a CNRS researcher, told AFP. According to this mechanic, an object can be in several states at the same time, which can overlap. This is the case with qubits, the basic brick in quantum computation: unlike conventional bits, which have only two possible states (0 or 1), qubits have an infinity of possible states. By being able to overlay them and then merge them together (link to each other), it is possible to perform several calculations at the same time.
>> Read also – French inventions could amaze the world
GPS, transistors, lasers, hard drives … the applications of quantum theory are numerous. “These are the basic components of the digital age,” explains a note from the Fondation Mines-Télécom. Evolution gradually emerged as a result of “the exploitation of this new understanding of the infinitely small”, Daniel Hennequin emphasizes: The transistor uses, for example, the quantum effects of electrons, the laser of photons.
Today, the most anticipated revolution is the universal quantum computer, the Holy Grail of computing. It would be able to process gigantic masses of data and would perform operations beyond the imagination, like Google, which says it has managed to calculate in three minutes where a conventional supercomputer would have taken … 10,000 years. The quantum computer would thus make it possible to solve problems that are today too complex for conventional machines, which would become obsolete. A major breakthrough would be to be able to run Shor’s algorithm, which is capable of breaking the encryption system that secures our transactions.
>> Read also – Artificial intelligence will increase growth in 2030
Other innovations are also expected with excitement in the communications sector, where quantum encryption (already used by some banks) allows for ultra-secure, even inviolable encryption. Finally, ultra-sensitive quantum sensors would allow extremely accurate measurements, such as gravity in space.
There are many obstacles left
These technologies encounter a physical obstacle called decoherence, which causes quantum properties to disappear upon contact with the outside world. In order to manipulate qubits, it is therefore necessary to select cold atoms, to prevent them from moving and to isolate them. But the more qubits there are, the more they lose their capabilities, and we can currently not complicate more than fifty of them. But to run Shor’s algorithm, for example, thousands would be needed. The universal quantum computer is therefore not for tomorrow.
>> Our service – Invest in innovative companies with high valuation potential before their listing
But as MP Paula Forteza’s report points out, there is a hybrid system that combines quantum and classical computing, which could be ready within a few years. Decoherence also hinders innovations in spatial communication, where the many interactions over the air prevent quantum continuity, generating transmission losses.
>> Sign up for Club Capital des Boursicoteurs on Facebook (click on the image)
Receive our latest news
Every morning, the information to keep in mind financial markets.