You've probably felt a rumble in your chest from a particularly loud bass note from a subwoofer — but this video from a trio of Japanese researchers takes the concept to a mesmerizing new level. Using super high-frequency ultrasonic beams, the researchers were able to not only lift up tiny polystyrene balls, but make them dance about in three dimensions, all to a soundtrack of "The Blue Danube."
Yoichi Ochiai, Takayuki Hoshi and Jun Rekimoto, from the University of Tokyo, are not the first to make objects levitate with sound. This team from China was able to get ants and even small fish to rise off a platform using sound waves. What's novel in this video is the ability to move them around once they were already levitating. In addition to choreographing the balls, which measured 0.6 and 2 mm in diameter, the video demonstrates acoustic levitation with small electrical components, pieces of wood, screws, water droplets and even the vapour trails from dry ice.
The researchers describe their methods in this paper uploaded to arXiv.org, a repository of physics, math and computer science articles.
As for the potential uses of the technology, the scientists end their paper with this tease about space: "It has not escaped our notice that our developed method for levitation under gravity suggests the possibility of developing a technology for handling objects under microgravity" — where people and objects appear weightless.
Via The Verge