Making Ice with Hot Water: Physicist Wins NSF CAREER Award for Studying an Unusual Phenomenon
Which makes ice-cubes faster, cold water or hot? The answer might surprise you.
In 1963, a Tanzanian scientist named Erasto Bartholomeo Mpemba observed that, under certain circumstances, hot water will freeze faster than cold. Today, scientists have observed that the phenomenon known as the Mpemba effect occurs not just in water but in polymers, magnetic alloys, and other physical systems. The phenomenon and the circumstances required to produce it are not fully understood, but assistant professor of physics Marija Vucelja’s efforts to do just that have won her a CAREER Award, the National Science Foundation’s most prestigious award for early-career faculty who serve as academic role models in research and education and who are leaders in advancing the mission of their departments.
Vucelja is a theoretical physicist with expertise in statistical physics. She is interested in how complex physical systems heat up and cool down or how their temperatures “relax” to match their environment.
The Mpemba effect is counterintuitive, Vucelja explains. “The surprise is that some rapid cooling protocols selectively open up relaxation shortcuts for the hot system. The result is that the hot system overtakes the warm system and equilibrates with the cold environment faster. My research is about finding out and quantifying when such remarkable shortcuts in thermal relaxation occur.”
In her search for answers, Vucelja is focusing on simple models of physical systems, and applying statistician’s tools of averages and probabilities to strip the complexity of the process down to its essential properties. The CAREER Award will allow her to develop a general theoretical framework for understanding and predicting how these relaxation shortcuts occur, which could lead to important advances in efficiency for manufacturing and metallurgy.
As an educator and a mother of two, Vucelja is also interested in making science more accessible to younger students. As a CAREER scholar, she is organizing opportunities for her and colleagues to reach out to area high schools, middle schools and the Boys and Girls Club of Central Virginia to develop programs that will make scientists and the work they do more visible.
Her aim, she explains, is to encourage kids “to be braver in their career choices and not to overlook STEM out of fear of mathematics.” She’s also interested in "improving how we communicate science to broader audiences.”
The goal is one her colleagues think is clear evidence of Vucelja’s importance to the future of research and education at UVA.
“Prof. Vucelja is fearless in both her choice of interesting research problems and her dedication to extending fundamental statistical physics methods into new regimes and across traditional disciplinary boundaries,” says Robert R. Jones, Francis H. Smith Professor and Chair of UVA’s Department of Physics. “The NSF CAREER Award is well-deserved recognition of Prof. Vucelja's previous work as well as her compelling plans for future research and developing middle and high-school students' interest in science. Prof. Vucelja exemplifies the commitment of Department of Physics faculty to creating new knowledge through research and providing the best possible learning opportunities for our students. We are honored to have her as a colleague.”