Vacuum Expectation Value

The Vacuum Expectation Value (VEV) refers to the average value of a quantum field in empty space, or "vacuum." In simpler terms, it’s a way to measure fields, like those for particles, even when no particles are present. In physics, especially in particle and field theory, a VEV can indicate the presence of spontaneous energy or symmetry breaking. This concept is crucial in understanding how fundamental forces and particles acquire mass, influencing the behavior of the universe at its most fundamental level. It highlights how empty space is not truly empty but filled with underlying properties.