C O N D E M A T O
n a hot, dry day in February, I arrive at Charles Sturt University just outside the New South Wales town of Wagga Wagga. I’m here to meet a special breed of physicist. One by one, they arrive at the shady outdoor seating area of a campus café. Seasoned, retired professors are joined by up-and-coming postdocs and freshfaced master’s students. Within half an hour, about 50 restless physicists crowd around tables adorned with bowls of chips and nuts. They begin to make conversation in an endearingly awkward way. There’s no small talk, no mention of the weather or the trip to Wagga Wagga. It’s straight into the physics. “What kind of plot matches your data?” “Are you using machine-learning algorithms to model the energies?” “What if you use a ferrous metal and fluctuate the magnetic field?” You may be wondering: Who are these people, what on Earth are they talking about and why are they all gathered in rural NSW on the banks of the Murrumbidgee River? Fair questions. These physicists conduct research in the fields of condensed matter physics and materials science, and they are attending an annual conference – affectionally called “Wagga” – organised by the Australian Institute of Physics. What, I hear you ask, is condensed matter physics? In the grand scheme of physics, this 84 COSMOS MAGAZINE
The most important field of physics you’ve never heard of. Evrim Yazgin reports.
field isn’t that well known. I completed my master’s at the University of Melbourne in theoretical condensed matter physics, and my family could only remember the field by referring to it as “condensed milk”. It was the joke that never grew old – for them. But while it doesn’t have the same recognition as, say, particle physics or astrophysics, condensed matter physics plays a critical role in the physical sciences and our daily lives. It’s been essential in developing semiconducting chips that led to modern computers, green technologies like solar panels, superconductors, nanotechnology, electronics, energy storage, magnetic materials and applications in medicine such as drug delivery. Wagga 2024, the 46th installation of the conference held in early February 2024, was a celebration of these aspects of condensed matter physics and materials science. As a science journalist, I was in heaven. Over four days of presentations, discussions and casual chats over lunch or coffee, I met a cast of interesting characters at the forefront of surprisingly diverse research into condensed matter physics. But before I introduce you to them, let’s delve into the intriguing history of this field.