Quantum Particle Defies the Law of Friction ⚡ экспресс
Superfluidity is the frictionless flow of a liquid. According to Landau, it is forbidden for one-dimensional bosonic systems. Yet, in an experiment with ultracold atoms, an impurity particle moved without friction through a one-dimensional Bose gas. The researchers accelerated the impurity from subsonic to supersonic speeds: at supersonic speeds, a shock wave formed, and then the system rapidly reached steady motion. The time to reach this state increased as the initial speed decreased. It's like a swimmer who, after a sharp start, creates a wave but then glides effortlessly—quantum effects completely eliminate resistance.
In ordinary environments, a body slows down due to friction. But in the quantum world, there is superfluidity: liquids flow without loss, like the famous helium at ultra-low temperatures. Previously, it was considered unthinkable for this to happen in a chain of particles—a one-dimensional system. However, physicists launched a foreign atom into a row of ultracold atoms. Like a bead passing through others strung on a thread: a free gap instantly appears ahead of it, and the chain closes up behind—without the slightest resistance. Even at supersonic speeds. An unexpected twist: the slower the initial push, the longer the braking lasted before uniform sliding. But ultimately, the motion always became perpetual and effortless. In the ordinary world, friction generates heat and disorder, but here—not a hint. This promises devices that transmit information without any loss.
🎯 If water could flow without friction, a thrown stone would create eternal ripples, and [tag:water]water[/tag] in a river would never stop.