I am very excited: I have just won a scholarship to take the Master's Degree in Quantum Science and Technologies in Barcelona.

In addition to learning more about the fascinating world of quantum physics, I will lay the foundation for my career in an expanding field that helps us better undertsand our world and could shape the technologies of the future.​

And that is not all: the scholarship will allow me to experience a new country and come into contact with a different culture.

I am an expert in cybersecurity. Nowadays, practically our whole life is connected to the internet: personal information, financial data, etc. In order to protect our privacy, we need to develop and improve the cryptographic methods we have. ​

Despite that it is unclear when these will be a reality, I am worried that quantum computers will jeopardise this security, but it is a relief to know that quantum physics also provides us  with tools to exchange information securely, regardless of how powerful computers are and will be.

I work for a bank responsible for securing our customers' financial transactions. Every day I think about what happens when quantum computers become powerful enough to break the encryption methods we currently rely on. I recently learned that researchers in quantum information theory are already developing new cryptographic protocols that would be secure even against a quantum computer  not because they are more complex, but because they are protected by the laws of physics themselves.​

For the first time, I felt like the security of our systems could be guaranteed by something more fundamental than mathematics alone.

If everything is made up of quantum particles (atoms, etc.), how can the macroscopic world not have the same "strange" properties as quantum particles?

The correspondence principle states that the classical behaviour of macroscopic objects is the statistical result of the random behaviour of a large number of quantum particles.

We do not yet know where the boundary between quantum and classical theory lies.

Quantum physics has allowed the birth of a first wave of technologies (such as lasers and transistors).

We can now control quantum particles at individual level and are arriving at the point of designing new disruptive technologies (second quantum revolution).

Examples: quantum computing, quantum cryptography, quantum simulators and quantum sensors.

Quantum communication uses quantum states, typically encoded in single photons, to transmit information in a fundamentally new way. Its most mature application today is quantum cryptography, which guarantees secure communication based on the laws of physics rather than on the assumed difficulty of mathematical problems. ​

Beyond secure data transmission, quantum communication also enables the distribution of entanglement between distant locations. In the future,it will form the backbone of large‑scale quantum networks, interconnecting quantum computers, sensors, and memories, and paving the way toward a global quantum internet.

Quantum Key Distribution (QKD) allows two distant users to generate a shared secret key using quantum states of light. Any attempt to eavesdrop on the communication inevitably disturbs these states and can therefore be detected. ​

QKD systems are already being deployed in secure communication networks for governments, banks, and critical infrastructures, and are being brought to the market by companies such as LuxQuanta, an ICFO spin‑off developing practical quantum‑safe communication solutions.​

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An open debate on quantum physics is how it is interpreted. The most common and oldest one (1925-1927) is the Copenhagen interpretation (which we have used in the Info Cards). However, there are other interpretations, such as the many-worlds interpretation (approx. 1960), which suggests that when we perform a measurement, all possible results appear in parallel universes, but we only observe one. One of the problems the interpretations have is that it is not clear whether they are experimentally verifiable.

Quantum physics is full of concepts that are difficult to communicate to the public: superposition, entanglement, wave-particle duality. These ideas are frequently misused in advertising, popular culture or pseudoscience.​

Does it matter if people misunderstand quantum physics, as long as they are generally supportive of research funding? Or does scientific literacy have a deeper value for society  and if so, whose responsibility is it to promote it?​

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Their applications in all fields of human activity will radically change our lives, just as electricity and electronics once did. We must invest as much as we can in their development, to make them commercially viable as soon as possible. 

We should not be fooled by illusory promises. We have gone very far with traditional technologies and we still have a long way to go: we should keep the current investment in quantum technologies at the same level. Let scientists do their work and continue to research, focusing on maintaining and improving the technologies that we already have. 

Research into quantum physics and its applications is positive, but we currently have other far more important and pressing issues, such as hunger, poverty, wars and terrorism. Let us maintain research, but invest our money to find solutions to the major problems our society has today.  

Quantum technologies are very promising, but if they are to be effective, they require solid knowledge of their foundations. We should invest in fundamental research: a better understanding of the foundations of quantum physics will naturally lead to the development of its applications.