Nobel Prize for scientists’ ‘groundbreaking’ work in quantum mechanics

4 Oct 2022

Illustration of Alain Aspect, John F Clauser and Anton Zeilinger. Image: Niklas Elmehed/Nobel Prize

John F Clauser, Alain Aspect and Anton Zeilinger conducted experiments using entangled quantum states, clearing the way for new tech based on quantum information.

Three scientists from the US, France and Austria have been awarded the 2022 Nobel Prize in Physics for their “groundbreaking experiments” in quantum mechanics.

John F Clauser, Alain Aspect and Anton Zeilinger have all been recognised for their research on entangled quantum states, which is where two particles behave like a single unit even when they are separated.

The Nobel Committee said today (4 October) that these experiments helped clear the way for new technology based on quantum information, which includes quantum computers, quantum networks and secure quantum encrypted communication.

“It has become increasingly clear that a new kind of quantum technology is emerging,” said Anders Irbäck, Nobel Committee for Physics chair.

“We can see that the laureates’ work with entangled states is of great importance, even beyond the fundamental questions about the interpretation of quantum mechanics.”

A key factor in the development of this field of research is how quantum mechanics allows two or more particles to exist in an entangled state. But for a long time, there were questions over whether the correlation was because the particles contained hidden variables that told them which result they should give in an experiment.

Northern Irish physicist John Stewart Bell developed a mathematical inequality in the 1960s, stating that if there are hidden variables, the correlation between the results of a large number of measurements will never exceed a certain value.

Clauser went on to develop the ideas of Bell. In a practical experiment, Clauser’s work supported quantum mechanics by clearly violating a Bell inequality.

The Nobel Committee said some loopholes remained after Clauser’s experiment, however. In another experiment, Aspect was able to switch the measurement settings after an entangled pair had left its source, so the setting that existed when they were emitted could not affect the result. This closed an important loophole in Clauser’s experiment.

Finally, Zeilinger and his research group demonstrated a phenomenon called quantum teleportation, which makes it possible to move a quantum state from one particle to another at a distance.

In 2010, the three scientists were awarded the Wolf Prize in Physics. They will now share the Nobel Prize for their experiments.

Who are they?

Clauser received his BSc in physics from the California Institute of Technology in 1964, his MA in physics in 1966 and his PhD in 1969 from Columbia University. Between 1969 and 1996, he worked at Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory and the University of California.

Aspect studied at ENS Cachan and Université Paris-Saclay, where he is currently a professor. He is a member of several science academies in France, Italy, US, Austria, Belgium and the UK.

Zeilinger is professor of physics at the University of Vienna and senior scientist at the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences.

Last year’s Nobel Prize in Physics was awarded Syukuro Manabe, Klaus Hasselmann and Giorgio Parisi for their “groundbreaking contributions” to our understanding of complex systems such as those behind global heating.

Yesterday (3 October), Swedish geneticist Svante Pääbo was awarded the 2022 Nobel Prize in Physiology or Medicine for his “pioneering research” in extinct hominins and human evolution.

10 things you need to know direct to your inbox every weekday. Sign up for the Daily Brief, Silicon Republic’s digest of essential sci-tech news.

Leigh Mc Gowran is a journalist with Silicon Republic