声速打破光速极限

美国物理学家设计了一种不同寻常的波导,使得声音在其中的传播速度超过光速。

Sound breaks the light barrier (Jan 12)

http://physicsweb.org/article/news/11/1/8

Nothing can travel faster than light except for sound. This is the claim of some US physicists, who say they have designed an unusual waveguide to make sound move at "superluminal" speeds (Appl. Phys. Lett. 90 014102).