A new University of Mississippi study shows that some sound waves don’t just move forward—they also move slightly to the side. Understanding this movement could help researchers develop more precise acoustic tools. Likun Zhang, associate professor of physics and astronomy and senior scientist at the National Center for Physical Acoustics, published his team’s study on the behavior of spiral sound waves in Physical Review Letters.

The experiment is the first measurement of the Hall Effect as it applies to acoustics. The Hall Effect occurs when something traveling forward—traditionally an electric current—is deflected slightly to the side by an external influence such as a magnetic field.

“About five years ago, our group extended the concept of the Hall Effect to acoustics, where we predicted that this would be the case,” Zhang said. “But this follow-up is the first time that we’ve been able to say, experimentally, ‘Here is that shift, and we can prove that it’s there.’”