Quantum Mpemba effect: hot cools faster, but only near absolute zero ⚡ экспресс
The Mpemba effect is a counterintuitive phenomenon where an initially hot system cools faster than a warm one. In this work, within the classical benchmark — an asymmetric bistable potential — the influence of quantization is investigated for the first time. It is shown that quantization shifts the Mpemba effect into the regime of ultracold temperatures, orders of magnitude below the classical thermal barrier crossing threshold. Moreover, quantization induces inverse and double inverse Mpemba effects, absent in classical dynamics. The results demonstrate that quantization provides a robust pathway to quantum versions of the Mpemba effect, inaccessible in classical regimes.
The Mpemba effect is a mystery where hot вода sometimes freezes faster than warm water. Usually this is attributed to how вода loses heat and энтропию (a measure of disorder). But in a glass of water, chaos prevents a precise model.
Physicists built a quantum model: a particle in a well with two depressions separated by a barrier. Like a ball on a hill with two dips: to roll from one to the other requires energy. In classical physics, a hot ball jumps more often. In the quantum world at ultra-low temperatures, the particle spreads into a wave and seeps through the barrier – without heating.
Surprise: the quantum Mpemba effect manifests not at room temperature, but only near absolute zero, where liquid гелий is used. Hot cools down faster, but only when thermal motion halts. Moreover, reverse paradoxes arise: cold overtakes hot, and sometimes a double reversal is observed – phenomena impossible in everyday life.
🎯 The effect is named after Tanzanian schoolboy Erasto Mpemba, who in 1963 noticed that hot ice cream mix freezes in the freezer faster than cold, and convinced physicists of this.