I am interested in answer in the following questions. Where in quantum electrodynamics Unruh radiation is hidden? How Feynmans graphs assign Unruh radiation? Of course, it is clear that acceleration in quantum electrodynamics is not uniform. But there are some photons that arise. Examples of acceleration of electron in QED are Compton effect or acceleration in electical field of nucleus. Article connected with this question is: http://www.hep.princeton.edu/~mcdonald/accel/unruhrad.pdf I read also something about nonlinear QED. Is this neccessary for this?