When your heart beats, blood courses through your veins in waves of pressure. These pressure waves manifest as your pulse, a regular rhythm unperturbed by the complex internal structure of the body. Scientists call such robust waves solitons, and in many ways they behave more like discrete particles than waves. Soliton theory may aid in the understanding of tsunamis, which—unlike other water waves—can sustain themselves over vast oceanic distances.
Solitons can arise in the quantum world as well. At most temperatures, gas atoms bounce around like billiard balls, colliding with each other and rocketing off into random directions. Near absolute zero, however, certain kinds of atoms suddenly start behaving according to the very different rules of quantum mechanics, and begin a kind of coordinated dance. Under pristine conditions, solitons can emerge inside these ultracold quantum fluids, surviving for several seconds.
Guided by this framework, the scientists also expected the impurities to act like friction and slow down the soliton. But surprisingly, dark solitons do not completely follow Einstein's rules. Instead of dragging down the soliton, collisions accelerated it to a point of destabilization. The soliton's speed limit is set by the speed of sound in the quantum fluid, and upon exceeding that limit it exploded into a puff of sound waves.
Read more at: https://phys.org/news/2017-02-destabilized-solitons.html#jCp