To illustrate the structure, consider a ferromagnet which is composed of atoms each equipped with a tiny magnet. When these magnets are lined up, the inside of the ferromagnet bears a strong analogy to the way empty space can be structured. Gauge vector fields that are sensitive to this structure of empty space can only propagate over a finite distance. Thus, they mediate short range interactions and acquire mass. Those fields that are not sensitive to the structure propagate unhindered. They remain massless and are responsible for the long range interactions. In this way, the mechanism accommodates within a single unified theory both short and long-range interactions.