gauge theory

Gauge theory is like a game that physicists play with tiny invisible things called particles, to explain how the universe works. It helps them to figure out how things stick together, why some things are attracted to one another, and why certain forces act the way they do. To play the game, physicists use something called a gauge—it's like a map that shows how particles are put together. By studying the map, physicists can understand how fields and forces work, and figure out why particles behave in certain ways.