  A sudden vertical impact on the mouth of a beer bottle generates a
compression wave that propagates through the glass towards the bottom. When
this wave reaches the base of the bottle, it is transmitted to the liquid as an
expansion wave that travels to free surface, where it bounces back as a
compression wave. This train of expansion-compression waves drives the forced
cavitation of existing air pockets, leading to their violent collapse. A cloud
of very small daughter bubbles are generated upon these collapses, that expand
much faster than their mothers due to their smaller size. These rapidly growing
bubble clusters effectively act as buoyancy sources, what leads to the
formation of bubble-laden plumes whose void fraction increases quickly by
several orders of magnitude, eventually turning most of the liquid into foam.
