Associate Professor Martin Weigt explored “The development of quantum mechanics and its influence on pure mathematics”.
Associate Professor Martin Weigt
He engaged his audience at the University’s Council Chambers on Friday 11 April by highlighting the impact of quantum science on global innovation and sustainable development.
And, while the topic itself may take many years of study to understand, Prof Weigt dotted his talk with real-world applications that a layperson could understand.
Hosted by the Faculty of Science, the address traced the surprising interplay between deep theoretical work and real-world technologies — from GPS and lasers to quantum computing — and showed how maths continues to boost innovation in a fast-evolving world.
Have you perhaps wondered what an algorithm is, for example? Prof Weigt suggested it could be seen as a recipe for a calculation.
He also included nuggets of history that reminded listeners that neither Newton’s laws nor Einstein’s relativity were handed down as finished products — they were built on new kinds of mathematics, invented out of necessity.
Albert Einstein did not win the Nobel Prize for Physics for his work on the equation E = MC2. Instead, it was awarded for his work on the photoelectric effect which helped to lay the groundwork for quantum theory.
Even earlier, when Sir Isaac Newton developed his theory of gravity – watching an apple fall from the tree – there was no such thing as calculus. He first had to invent the branch of maths that we today know as calculus to solve the problem of why the apple fell, and then use this to develop his theory.
The lecture marked the first in a series of events marking 2025 as the International Year of Quantum Science and Technology.
“The development of quantum mechanics really started in 1925 with Werner Heisenberg's matrix mechanics, and the equivalent wave mechanics formulation by Erwin Schrodinger in 1926,” Prof Weigt explained.
Jumping 100 years forward in time, although these theories still shape school curricula, they have evolved dramatically.
“Not only do these theories incorporate our understanding of atomic structure by Rutherford and Bohr, and the weird and counter-intuitive things going on in quantum physics, but they also had a profound impact on some of the development of pure mathematics.
“A symbiosis between quantum mechanics and pure mathematics has developed ever since.”
He spelt out the difference between classical and quantum physics, saying the former was predictable and deterministic.
“In classical physics, the physics we're familiar with, all objects and fields have objective existence.
“If you are looking at the night sky, for example, and you see Jupiter or Saturn orbiting the Sun, this can be simulated in a typical planetarium dome. It is predictable, and deterministic. Even if I cannot see it, right now Jupiter is still floating around the Sun. It is there.
“Quantum physics does not work in this way: if I don't look at it, and I don't observe it, then it doesn't actually have an objective reality. It is like it almost doesn't exist. It is very weird!”
Dean of Science Professor Zenixole Tshentu, left, and Associate Professor Martin Weigt. (Images by Gillian McAinsh)
Faculty of Science Executive Dean Prof Zenixole Tshentu said that South Africa had been at the forefront of the push for the introduction of an International Year of Quantum Science and Technology.
It aligns with the University’s drive to generate cutting edge knowledge for a sustainable future, in service of society.
Nelson Mandela University also hosts a node of the National Institute for Theoretical and Computational Sciences (NITheCS).
The University’s Deputy Vice-Chancellor for Research, Innovation and Internationalisation, Prof Azwinndini Muronga, heads the Eastern Cape and Free State node of NITheCS, which seeks to build human and research capacity in theoretical and computational sciences.
Under this umbrella, Prof Weigt is also developing the Mandela Institute for Theoretical and Computational Sciences (MITheCS) to further strengthen resources in the field.
Prof Weigt is an NRF-rated researcher who has specialised in functional analysis, unbounded operations and topological algebras, and their applications to mathematical physics.
He completed his BSc honours and master’s degrees at Stellenbosch University and his doctorate at the University of Cape Town before going on to postdoctoral studies at the University of Athens in Greece.
Prof Weigt closed his talk by highlighting the ongoing need for theoretical work and the mysteries that remain.
Despite all the theories and equations at the heart of science, there were still gaps that need to be filled, which made the work of mathematicians and physicists important, so that science can better serve society.
“Who knows? Time will tell what we come up with in future!” he said.