David Hambling
A US company claims it is ready to build a microwave ray gun able to beam sounds directly into people’s heads.
The device - dubbed MEDUSA (Mob Excess Deterrent Using Silent Audio) - exploits the microwave audio effect, in which short microwave pulses rapidly heat tissue, causing a shockwave inside the skull that can be detected by the ears. A series of pulses can be transmitted to produce recognisable sounds.
The device is aimed for military or crowd-control applications, but may have other uses.