Quantum Gases2026-04-302 minarXiv:2604.27489expressWhen the Obstacle VanishesA stone falls into a pond, and ripples spread across the water. But if the stone is very small and the water is not quite ordinary, the ripples pass right through it, as if it weren't there.Keisuke Fujii·Daichi Kagamihara·Masaru Hongotunnel effectGeorge GamowLeo EsakiLev Landauquantum tunnelingsuperfluidityturbulenceinterferencesuperconductivity👍👎☆SimplePopularAdvanced