The tractor beam, a science-fiction staple that can pull in spaceships and other things remotely, is entering the realm of reality.
Researchers on Tuesday said they have developed a tractor beam that uses high-amplitude sound waves to levitate, move and rotate small objects without making contact with them. They envisioned medical and other applications for the device.
"As a mechanical wave, sound can exert significant forces on objects. Just remember the last time you were in a concert and your chest was vibrating with the music," said study lead author Asier Marzo of Britain's University of Bristol and Spain's Public University of Navarre.