Pair production is a process in physics where energy is converted into matter. This occurs when a high-energy photon, such as a gamma ray, interacts with a strong electromagnetic field, typically near a nucleus. The energy of the photon is transformed into a particle-antiparticle pair, usually an electron and its antiparticle, a positron. The conservation laws of energy and momentum must be satisfied during pair production. This means that the energy of the incoming photon must be at least equal to the combined rest mass energy of the created particles, which is about 1.022 MeV for an electron-positron pair.