I know that free electrons can't absorb photons. It is, however, known that electric forces can accelerate electrons. But if electric interactions are merely an exchange of virtual photons, how can the electron even absorb the virtual photon in the first place? I mean, before the interaction, the electron was free. So it shouldn't absorb the photon.
I suppose this has something to do with the nature of virtual photons. But I'm not sure.