A group of dancers spins in sync: each instantly picks up the neighbor's move. That's how Bose–Einstein condensate behaves: a crowd of spins merges into a common field and forms a single superposition — a frictionless flow, like in a superconductor.

Even a gentle heat throws off the rhythm. For spin-½, a single backward flip wrecks the dance — physicists call it quantum decoherence, and disorder spikes sharply. Calculations within quantum thermodynamics confirm: when spin is large, isolated glitches go unnoticed, like a wrong note in a vast choir. The key ideas trace back to Lev Landau and Satyendra Nath Bose.

A surprising twist: if spin were infinitely large, disruptions would vanish entirely — the current would flow like water with zero viscosity at any temperature.