Question: How does the ultrasound levitation work? Is there the possibility of lifting something made of glass or will it just break? What are you planing on lifting? Could you revolutionise travel with it or just allow you to make a really cool floating exhibit?

Luke Cox answered on 27 Nov 2020:

All sound is simply pressure waves and pressure is simply a force over an area. When you hear something that is simply the pressure waves exerting a force on your eardrums. If we make the pressure field high enough we can counteract the force of gravity and lift objects up.

We certainly could levitate glass objects using ultrasound, one of the biggest advantages of using ultrasound is it is largely material independent. I actually know someone who is investigating how we can form glass whilst levitating it using a high powered laser.

We’re unlikely to use it for travel because when you can choose the material magnetic levitation is much more efficient. We can definitely make floating exhibitions, here is some people who have created a volumetric display https://www.youtube.com/watch?v=jOnxr9Ez_Kc