For nearly two centuries, scientists have known that protons move through water not by drifting but by leaping—a restless molecular dance called the Grotthuss mechanism that underlies everything from battery chemistry to the electrical language of living cells. An international team led by Heidelberg University has now built the most precise quantum simulation ever attempted of this process, tracking 51 coupled vibrations simultaneously to reveal that it is the subtle asymmetry of surrounding water molecules, not any idealized structure, that governs each proton's hop. The finding reframes wat