Quantum Particle Defies the Law of Friction ⚡ экспресс
Frictionless motion in a fluid is the hallmark of superfluidity. Landau argued that kinematic constraints forbid superfluid behavior in one-dimensional bosonic systems. In an experiment with ultracold atoms, a microscopic impurity propagated without friction through a strongly interacting one-dimensional Bose gas, contradicting established beliefs. The impurity was given initial speeds ranging from subsonic to supersonic, and then its dynamics were tracked. At supersonic speeds, a shock wave formed and an extremely rapid relaxation to a steady state was observed, with the relaxation time increasing as the speed decreased. In the steady state, the impurity continued to move at a finite speed. These results show how quantum effects eliminate dissipation for a microscopic object in a quantum fluid, opening new perspectives for understanding the propagation of matter and information in the quantum world.
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.