Nobel duo makes sense of quantum’s ‘spooky’ world

One tall, with an unruly shock of silver hair that invites comparison with Albert Einstein. The other shorter, sporting a splendidly curled grey moustache and with a mischievous twinkle in his eyes.

Dressed in short-sleeved shirts, Nobel physics laureates John Martinis and Alain Aspect could almost pass for a pair of science nerds. But, as audiences in South Africa discovered recently, both have a knack for making seriously difficult science approachable.

The modern theory of quantum mechanics celebrated its centenary last year. Yet its strange behaviour still confounds ordinary intuition. Albert Einstein famously objected to what he called “spooky action at a distance”.

Quantum mechanics already underpins many technologies on which modern life depends. Now researchers are learning to exploit its stranger properties in a second technological revolution, including quantum computing.

That was the focus of the sixth Nobel in Africa symposium, hosted by the Stellenbosch Institute for Advanced Study (STIAS) at the end of October. It marked a return to physics – the subject of the inaugural 2022 gathering – and opened a second series of Nobel symposia on African soil.

Nobel in Africa

The initiative began in 2022, when STIAS became the first institution outside Scandinavia to host a Nobel Symposium. Presented in partnership with Stellenbosch University (SU), under the auspices of the Nobel Foundation and the Royal Swedish Academy of Sciences, it is supported by Wallenberg Foundations.

Its first five symposia covered physics, chemistry, economic sciences, physiology or medicine, and literature – five of the Nobel Prize fields.

STIAS Director Professor Edward Kirumira announced that the initiative would, in future, also extend to the sixth field, peace, through collaboration with the Norwegian Nobel Committee.

He drew applause when he noted that South African jurist Navi Pillay had recently been named the 2026 Nobel Peace Prize laureate.

The latest symposium brought international specialists together to assess what quantum computers can realistically achieve, how to scale them up and what obstacles remain.

SU Vice-Chancellor Professor Deresh Ramjugernath told the public audience that Africa should not simply observe the next technological revolution from afar: “Our researchers and our students must be part of shaping it.”

‘Strange, but not irrational’

Aspect delivered the SU Chancellor’s Public Lecture on 27 October with energetic gestures, dry humour and expressive French-accented English.

Recalling his three years teaching future physics teachers in Cameroon in the early 1970s, Aspect brought a personal African connection to the occasion.

It was during this period, he told participants, that he deepened his understanding of quantum mechanics by studying a textbook by French physicist Claude Cohen-Tannoudji – knowledge that helped prepare him for his later Nobel-winning experiments.

“Quantum physics is strange, but it is not irrational,” Aspect reassured his audience as he introduced the theme of his Tuesday evening lecture, ‘Two Quantum Revolutions’.

The first arose from the discovery that light and matter behave as both waves and particles, opening the way to an understanding of atoms and the invention of transistors, lasers and integrated circuits.

The second centres on entanglement: quantum objects can have linked properties even when separated by enormous distances. Individual measurements seem random, yet the correlations between them defy what classical explanations allow.

Aspect illustrated entanglement with an imaginary “tricky coin toss”. Suppose “Alice” and “Bob” each toss a coin, far apart. The results appear random, but imagine that every time Alice gets heads, Bob also gets heads, and whenever she gets tails, so does he.

In the quantum world, entangled particles can display similarly extraordinary correlations.

“The goal of physics is to understand the tricks of nature,” he said.

Einstein believed that entangled particles must possess hidden properties that explained their apparent connection. Niels Bohr disagreed. For decades, the dispute seemed philosophical, until, in 1964, physicist John Bell devised a mathematical test that could distinguish between their competing interpretations.

Aspect’s groundbreaking experiments with entangled photons at the Institut d’Optique near Paris in 1981-82 helped settle the argument – and showed that Einstein had been wrong, at least about this aspect of quantum physics.

By changing the measurement settings while the photons were in flight, he demonstrated that their behaviour could not be explained by pre-existing properties acting locally, as Einstein had envisaged.

The findings confirmed one of quantum mechanics’ strangest predictions and helped lay the foundations of modern quantum information science.

Aspect shared the 2022 Nobel Prize in Physics with John Clauser, who conducted earlier pioneering experiments, and Anton Zeilinger, who extended the research.

Although entangled particles exhibit seemingly instantaneous correlations across vast distances, they cannot be used to send messages faster than light. But entanglement is the basis of technologies such as quantum-secured communication.

And, as Aspect mischievously reminded his audience, quantum teleportation does not mean “transporting the rector from one place to another” – it is a quantum state that is transferred using entanglement.

What was once a foundational puzzle is becoming practical science. Aspect described quantum communication, highly sensitive measurement devices and quantum simulation, while cautioning that general-purpose quantum computers are still a work in progress.

Nature like a ‘nervous banker’

Martinis had delivered the opening public lecture on Monday, 26 October. Where Aspect traced the intellectual revolution, the American experimentalist followed the journey from fundamental experiments to the engineering challenge of building a useful quantum computer.

His doctoral research at the University of California, Berkeley, under John Clarke and alongside Michel Devoret, asked whether the rules of quantum mechanics apply to electrical circuits large enough to be seen and handled, rather than only to individual particles.

One of those rules is quantum tunnelling, the seemingly impossible ability of a quantum system to cross a barrier it could not overcome according to classical physics.

Martinis offered a striking analogy: nature behaves like a “nervous banker”, lending a system energy for an exceedingly brief moment before calling in the loan.

In experiments in 1984-85, Martinis and his colleagues demonstrated that quantum mechanics was not confined to the world of individual particles. An electrical circuit involving enormous numbers of electrons could behave as a single quantum system, tunnelling through an energy barrier and absorbing energy only in discrete amounts.

It was groundbreaking evidence that the strange rules of the microscopic quantum world could also govern larger, engineered systems.

The discovery earned Clarke, Devoret and Martinis the 2025 Nobel Prize in Physics – not for inventing quantum computing, but for showing that quantum behaviour could be demonstrated and controlled in an electrical circuit.

Those experiments helped prepare the ground for quantum bits, or qubits. Unlike ordinary computer bits, which are either zero or one, a qubit can exist in a superposition of states. Combining and manipulating qubits opens up radically different kinds of computation, although not a shortcut to every problem.

One promising application is chemistry. Martinis explained how powerful quantum computers could eventually simulate the behaviour of molecules, helping scientists design new materials and drugs while reducing the need for costly and lengthy laboratory experiments.

Martinis later took his research team from the University of California, Santa Barbara, to Google, where they developed a 53-qubit processor that, in 2019, performed a specialised task beyond what was then practical for conventional computers.

It was a milestone, but not yet a general-purpose quantum computer. Today the challenge is to control errors, integrate bulky supporting hardware and scale the technology.

Martinis compared the field with conventional computing in the 1960s, before components were packed into microchips. He showed a hand-sized, 3D-printed model of what a future integrated system might look like – not a working machine, but a vision of what engineers must build.

Quantum in Africa

The technological race is also on in Africa.

SU researchers have demonstrated quantum-secured communications, including a record 12,900km satellite link with Chinese collaborators, as University World News reported in 2025.

South Africa has developed a national quantum research roadmap, with an emphasis on skills and software rather than manufacturing large quantum computers.

Asked by symposium co-convenor Professor Francesco Petruccione where countries should direct their investment in quantum technology, Aspect replied: “My advice to governments is to support the technology which is most advanced at the moment in their country.”

He cautioned against spreading limited resources across competing approaches to building quantum computers, when no one yet knows which will prevail. The symposium programme devoted sessions to five such approaches – using ion traps, superconducting circuits, neutral atoms, semiconductors or photons.

Nobel-winning PhD theses

Both laureates won Nobel Prizes for experiments carried out during their doctoral research four decades earlier.

“John Martinis and myself, we got Nobel Prizes for our theses,” Aspect said. “So if you have a good thesis, maybe after 40 years you get a Nobel Prize!”

But behind the joke was serious advice to young researchers: important scientific discoveries can begin with the questions they pursue as students, even when the significance of their work is not immediately recognised.

Martinis stressed the importance of mentors and of asking the right questions. His own doctoral experiments had encountered setbacks before the team succeeded in excluding interference that was obscuring the quantum effects they sought to measure.

Aspect urged students not to shy away from unconventional research, even if others dismissed it as “crackpot physics”.

But an unpopular idea was not necessarily a good one, he pointed out. Scientists still had to convince their peers that a question was worth pursuing.

‘Wonderful opportunity’

For Cameroonian physicist Dr Etienne Wamba, the symposium offered a rare chance to engage directly with world-leading researchers.

A lecturer at the University of Buea who researches quantum simulation and the behaviour of ultracold atoms, Wamba is a 2020 STIAS Iso Lomso Fellow and has taught across the African Institute for Mathematical Sciences ([url=https://aims.ac.za/]AIMS) network.

He told University World News the symposium was “a wonderful opportunity to bring top world-class researchers to the continent of Africa”.

The laureates’ message also resonated beyond physics. Nigerian forest ecologist Iveren Abiem, of the University of Jos and a 2026 Iso Lomso Fellow at STIAS, told University World News she was struck by the laureates’ enthusiasm and the example they set.

“We may not all win the Nobel, but we all must be thinking of doing important work that makes an impact, whether at community level or on the whole world,” she said.

Trust in science

For Nobel Foundation Chair Professor Astrid Söderbergh Widding, the value of the prizes extends beyond recognising exceptional achievements. Their history and rigorous selection process, she said, inspire “a sense of wonder about science and a desire for deeper knowledge”.

“Both are important drivers of trust, perhaps more important than ever in times of distrust and uncertainty.”