Quantum computing: understanding today the tech that could change tomorrow.

Although still in an experimental phase, quantum computing could generate up to $850 billion in value by 2040, by solving mathematical problems that are currently beyond our capabilities. An ongoing global promise, but one that is, as yet, far from being kept.

Quantum computing: a look behind the curtain of the silent revolution

Quantum computing is quite different from artificial intelligence. Unlike the latter, which exploits massive amounts of data, quantum computing is based on a different premise in the sense that it is set to change the very way we calculate as we know it – a truly disruptive technology that could have significant implications for science, industry and finance.

In concrete terms, quantum computers use a different computing system to current machines. Classical computers manipulate ‘bits’, which may have a value of either 0 or 1. Quantum computers, on the other hand, use ‘qubits’ (the basic unit of information used to encode data in quantum computing), which may hold both values simultaneously. This property, as per the laws of quantum physics, is called superposition. It allows quantum computers to process a huge number of possibilities at once, which considerably increases their computing speed. Quantum computers also possess another property: entanglement. This is a phenomenon by which two qubits can instantly influence each other’s state, even at a distance.

Quantum computing could be used in particular to simulate reactions between complex molecules, model entire economic systems, and anticipate crisis scenarios – tasks that classical computers, even the most powerful, struggle to complete without having to oversimplify them.

By making it possible to model systems that were previously out of reach, quantum computing is not just pushing the boundaries of computing, it could also redefine our ability to understand, anticipate and transform reality. This new approach would enable us to solve previously unsolvable problems. Quantum computing could be used in particular to simulate reactions between complex molecules, model entire economic systems, and anticipate crisis scenarios – tasks that classical computers, even the most powerful, struggle to complete without having to oversimplify them.

Today, quantum computers are still unstable and highly sensitive to external disturbances. For example, qubits (the basic unit of information used to encode data in quantum computing) only function when isolated from even the slightest noise and maintained at -273°C, close to absolute zero, the coldest possible temperature in the universe, where thermal motion ceases. This cryogenic cooling, which is both costly and complex, is one of the many technical challenges that must be overcome. However, progress is being made at a rapid pace, driven by huge investments and a global race for innovation. Giants such as IBM, Google, Amazon and Microsoft are devoting considerable resources to stabilising machines, improving error correction and preparing for the industrialisation of this technology – each with the ambition of being the first to cross the threshold of quantum advantage.

A promising yet experimental technology

The theoretical power of quantum technology is beginning to gradually unfold, with a view to supporting key sectors of the economy in the near future. In healthcare, it paves the way for molecular simulations with unprecedented levels of accuracy, for instance, today, testing a new molecule against a biological target involves approximate calculations or lengthy laboratory trials. Quantum technology makes it possible to simulate interactions between molecules at the atomic level, which will accelerate drug development, thereby reducing costs while treating certain diseases more effectively.

In industry, this capability will enable the optimisation of complex chemical or energy processes. Companies like Air Liquide and C12 Quantum Electronics are working, for example, on optimising hydrogen production, a strategic issue in the energy transition.

In finance, quantum computing is of interest for its ability to simulate extreme scenarios, refine risk models and detect fraud by cross-referencing large amounts of data.

More generally, quantum computing is challenging traditional computer architectures. While it is not intended to replace traditional IT, it could significantly expand its scope, which requires advance preparation. It is with this in mind that public and private initiatives are multiplying across Europe, particularly in Luxembourg, which is also declaring its intentions and aiming to be at the forefront of emerging technologies in the coming decade. After launching the MeluXina supercomputer, followed by its AI version, the country is now preparing MeluXina-Q, its first quantum computer, which is scheduled for launch in 2026. Luxembourg is also a partner in the European EuroQCI project, which aims to establish a secure quantum communication infrastructure across the continent.

A shift already initiated by the major powers

All over the world, investment dynamics are intensifying to drive the quantum revolution. In Europe, the Quantum Flagship programme plans to invest more than €550 million in public funding by 2027. Major European industrial and energy groups are among the pioneers, including Airbus, Thales and TotalEnergies.

But beware, this race will not benefit everyone. The international consulting firm Boston Consulting Group (BCG) warns: 90% of companies will remain on the sidelines. According to them, only the most proactive 10% of companies, which will have invested on time and structured their strategy well in advance, will gain a real competitive advantage from quantum computing.

Quantum technology will not replace everything, and certainly not in the immediate future. But in areas where it will be applicable, it will certainly change the rules of the game, in some cases, very abruptly.