It results from the creation of a particle pair near a black hole.  
It is a natural consequence of postrelativity for the Fock space.  Following the evolution of the initial Minkowski vacuum, when the Unruh state coincides with the Hartle state, it can be seen by observers at rest with respect to the body that produces it.  It results from the creation of a particle pair near a black hole.  One particle falls into the black hole and the other, FTP, moves away as what type of radiation named for the British physicist who proposed it?
It is a natural consequence of postrelativity for the Fock space.  
Hawking radiation