How quantum information gets scrambled in fully connected spin systems

Researchers tracked how quantum information scrambles in the SYK model, where every particle interacts with every other. Entanglement measures revealed a universal pattern: information grows rapidly then saturates to maximum randomness, with the rate depending on interaction strength and system size. Mixed-state correlations display a Page-curve signature—information born at one edge, spreads, then dies—suggesting scrambling follows predictable physical rules.