The Wilson Loop

The Wilson loop is a mathematical tool used in quantum physics, especially in studying the forces that hold atomic particles together. Imagine drawing a closed loop in space, then measuring how a particle's wave function changes when it moves around this loop. The result reveals information about the underlying fields and forces, such as the presence of invisible "strings" like those in quantum chromodynamics that bind quarks. Essentially, the Wilson loop helps physicists understand how particles interact through fundamental forces by translating complex quantum behavior into a calculable loop measurement.