Researchers at ETH Zurich have managed to make sound waves travel only in one direction. In the future, this method could also be used in technical applications with electromagnetic waves. Water, ...

Flaps perform essential jobs. From pumping hearts to revving engines, flaps help fluid flow in one direction. Without them, keeping liquids going in the right direction is challenging to do.

In context: Sound waves typically propagate in forward and backward directions. This natural movement is problematic in some situations where unwanted reflections cause interference or reduced ...