Why do quantum systems remember their past? ⚡ экспресс
In the PXP model, realized with arrays of Rydberg atoms, we investigated the emergence of local 'memory' of the initial state. Most eigenstates obey the Eigenstate Thermalization Hypothesis, but exceptions—quantum many-body scars—break thermalization. The study probed local memory persistence using local fidelity and dynamics of local observables. It showed that two initial state types—θ-symmetric and blockaded—display robust local reminiscence: fidelity values near unity, with fluctuations suppressed as system size grows. These findings indicate that non-ergodic regimes can sustain stable local memory against complex global dynamics, offering fresh insight into quantum scars and constrained-system dynamics.
Usually any disturbance in the quantum world disperses like ripples on water. But in systems with the rule 'no two can be excited next to each other,' special patterns emerge — quantum scars. They don't fade, like waves frozen in time.
Scientists studied two types of initial configurations of these scars and found that even tiny parts of the system almost perfectly replicate the original state. As the system grows, random deviations only diminish. Like a photograph frozen into a dynamic movie, local memory resists chaos.
This changes our understanding of entropy and disorder and paves the way to ultra-stable quantum computers. Experiments with spectroscopy already confirm such ideas, bringing us closer to controlling quantum memory.
🎯 Atoms in such experiments are comparable in size to bacteria — up to thousandths of a millimeter.
🎬 In Peter Watts' sci-fi novel 'Blindsight,' an alien ship uses quantum states to preserve consciousness — perhaps quantum scars could form the basis of such technology.