Queen of Equations

Nalini Joshi’s coronation as New South Wales’s Scientist of the Year signals that in the quantum age, mathematics may be civilization's most strategic science.

The 2025 Premier’s Prizes for Science, held beneath the chandeliers of Government House in Sydney, offered an implicit rebuke to the age of scientific celebrity. New South Wales’s top honour did not go to a physicist chasing particles, a chemist inventing materials or a doctor fighting disease, but to a mathematician. Nalini Joshi, the Payne-Scott Professor and Chair of Applied Mathematics at the University of Sydney, became the first mathematician to be named Scientist of the Year. In an era mesmerised by artificial intelligence and quantum hardware, the decision made a subtler point that progress depends less on machines than on the mathematics that makes them possible.

Joshi is not the sort of mathematician who confines herself to blackboards and abstraction for its own sake. She is a world leader in integrable systems, a rarefied corner of mathematics that studies highly structured equations whose solutions can be written down exactly. These systems govern everything from the propagation of light through fibre-optic cables to the behaviour of waves in the atmosphere. Climate models, fluid dynamics and parts of theoretical physics all rest on the same deep mathematical scaffolding that Joshi has spent her career exploring.

Her elevation to Scientist of the Year therefore carries a wider message. New South Wales is not merely rewarding past brilliance; it is betting that the future will be written in mathematics. That future, as Joshi repeatedly warns, is arriving faster than policymakers and industry are prepared for. The most urgent frontier is quantum technology. Quantum computers promise to transform drug discovery, materials science and logistics. They also threaten to make today’s cryptographic systems fatally vulnerable.

“Mathematics is central to securing our quantum future,” she insists.

Joshi occupies a rare position at the intersection of pure theory and applied urgency. Her work in integrable systems probes the deep symmetries that make certain equations solvable, a property that turns out to be vital in understanding complex, real-world phenomena. In quantum cryptography, those same symmetries and structures are what allow information to be encoded and protected in fundamentally new ways.

Her career has been as path-breaking as her research. She was the first woman ever appointed Professor of Mathematics at the University of Sydney, an institution she knows intimately, having been both an undergraduate and a University Medallist there. After completing her doctorate at Princeton University - still the Mecca of global mathematics - she returned to Australia and steadily built an international reputation. From 2019 to 2022 she served as the first Australian Vice-President of the International Mathematical Union, the discipline’s most powerful global body, a post that placed her at the centre of decisions about everything from research priorities to the governance of major prizes.

She is a Fellow of the Australian Academy of Science, an honorary member of the London Mathematical Society, and was appointed an Officer of the Order of Australia in 2016 for her services to mathematics. In 2018 she won the Eureka Prize for Outstanding Mentorship of Young Researchers, recognition not of a theorem but of a human legacy. Students and early-career mathematicians speak of her with a mixture of reverence and affection, describing a mentor who combines intellectual rigour with a fierce commitment to widening the gates of a discipline that has long been unwelcoming to women and minorities.

Mathematics, for all its claims to universality, has been historically narrow in who gets to participate. Joshi, an Indian-origin scholar who rose to the top of Australian academia, has become a visible counter-example. Her appointment as Scientist of the Year has been celebrated not just in Sydney but in India and across the global scientific diaspora.

While the 2025 prizes also honoured other luminaries like Anita Ho-Baillie for her work on perovskite solar cells and Paul Keall for innovations in cancer therapy, Joshi’s award stood out for its symbolism. In an era obsessed with tangible breakthroughs, it suggested that the equations that describe the world are as important as the devices that exploit it.

For Joshi, the accolade is less a culmination than a platform. The quantum age she describes is not a distant speculation but an approaching reality, and it will need mathematicians in far greater numbers than today. If her career proves anything, it is that the hardest problems of the future will be solved not only in laboratories but in the elegant, unforgiving language of mathematics.