Always cool watching items defying gravity in by whatever means.
Boffins at the University of Tokyo have come up with an array that lets objects be manipulated in three dimensions using sound only. By shaping and orienting sound in the form of standing waves, the system is flexible enough to levitate solid objects as well as drops of liquid. The principle is also known as acoustic levitation.
As the Wired article says, the principles exhibited here have been known for some time. However, this experiment shows what fine control can be achieved in three dimensions.
If you’re wondering what the applications are for such things, then ponder no more. There are rumours this sort of technology will find it’s way into applications such as replacing windscreen (a.k.a. windshield) wipers. Apparently it’s already deployed in fighter jets. It had occured to me many times past that technologies for clearing away rain haven’t so vastly changed in about 100 years, mainly only our ways for controlling wipers themselves.
Anyway, this is exactly the kind of science many of us would have loved to get involved with at school. Who knows, some of us might actually have been motivated to dabble in physics a little more and perhaps better appreciate some principles. Fun is a good way to learn :-)