|The radiation produced by a black hole when quantum mechanical effects are taken into account. According to quantum physics, large fluctuations in the vacuum energy occurs for brief moments of time. Thereby virtual particle-antiparticle pairs are created from vacuum and annihilated. If pair production happens just outside the event horizon of a black hole, as soon as these particles are formed they would both experience drastically different gravitational attractions due to the sharp gradient of force close to the black hole. One particle will accelerate toward the black hole and its partner will escape into space. The black hole used some of its gravitational energy to produce these two particles, so it loses some of its mass if a particle escapes. This gradual loss of mass over time means the black hole eventually evaporates out of existence.