“We all use the quantum world every day”
In 1925, physicist Werner Heisenberg published a seminal paper in which he mathematically described quantum mechanics, the study of physics at the atomic and subatomic levels. 100 years later, the United Nations, the German Physical Society (DPG) and physics societies worldwide are celebrating this anniversary with the “International Year of Quantum Science and Technology”. In an interview with Christina Hoppenbrock, quantum physicist Professor Carsten Schuck from the University of Münster explains why classical physics is not enough to understand the world.
Quantum physics allows us to explain observable phenomena, such as the spectra of atoms or wave-particle duality, which cannot be described by classical physics. If you want to understand how a laser works, classical physics is no longer sufficient and you have to fall back on concepts from quantum physics.
How does the quantum world play a role in our everyday lives?
It is a fundamental basis of observable nature. If you look at nature at very small scales, for example at the level of individual atoms, electrons and photons, you will see that quantum effects are very pronounced. In our everyday macroscopic world, however, classical physics is perfectly adequate to explain how an apple falls from a tree, because quantum effects are usually infinitesimally small and barely perceptible to us. Yet we all use the quantum world every day, often for hours on end. Only the laser mentioned above makes it possible today to exchange information via the Internet. It is only thanks to atomic clocks that we can navigate using GPS signals, and the chips in our computers and mobile phones only work because we have learned to make clever use of quantum effects.
Can quantum technologies help solve societal problems?
Historically, quantum technologies are a very recent development, with the aim of controlling quantum systems such as atoms, photons or superconducting circuits so well that information can be encoded in special quantum states. This has serious implications for the processing and exchange of information and for the question of what information can be extracted from measurements. Much hope is pinned on the development of quantum computers, which, according to current knowledge, could solve some mathematical problems dramatically faster than the “classical” computers currently in use. It is not yet clear how these quantum computers can be technologically realised on a relevant scale, and which societal problems can be traced back to the mathematical problems that quantum computers can solve particularly quickly. However, huge efforts are being made around the world to build such computers, in the hope of making advances in optimisation problems, drug development, materials science and climate calculations.
What fascinates you about your work in quantum technology?
I am primarily fascinated by controlling the mostly hidden properties of quantum systems and making them usable for meaningful applications. I am particularly interested in applications where only quantum technology can provide solutions. Current classical computers, networks or sensors will never be able to achieve anything even remotely comparable.
This article is taken from the university newspaper wissen|leben No. 2, 2 April 2025.
A programme of lectures, workshops and concerts for different age groups will be held at the University and in the city of Münster during the IYQ: The University of Münster’s “Kinder- und Jugenduni” (Q.UNI) and the “MExLab Physik” experimental laboratory offer interactive events and hands-on activities for schoolchildren throughout the year. On Instagram (@frag_sophie), the Innovation Office (AFO) presents famous “quantum minds” on the theme of #quantum100. The Faculty of Physics invites interested members of the public to the open lecture series “Physics at lunch time”, which is all about quantum physics. Professor Gernot Münster will kick off the series on 12 April at 12 noon with a talk on the history of quantum physics (Fürstenberghaus, Lecture Hall F 2, Domplatz 20-22). Save the date: The all-day closing event of the German Physical Society (DPG) will take place on 15 November in Halle Münsterland.