Main Question or Discussion Point
I am confused about the idea of mass renormalization in quantum field theory. Firstly, in case of charge renormalization there is a picture where you have a swarm of particle antiparticle pairs round the electron and hence depending on the energy of your probe , the charge gets renormalized .But somehow there is no such analogous picture in the mass renormalization. The way in which this is introduced in the texts that I have seen is that they calculate the corrections to the propagator coming from higher order feynman diagrams and include the cutoff dependent quantities that you get in the process inside the mass and field ..hence the renormalized mass becomes cutoff dependent . Does this imply that in a different scale, we will record a different mass ?? Another doubt is the distinction between bare and physical perturbation theory...in physical perturbation theory , we sort of perturb around the lagrangian with renormalized masses and coupling constants by including counterterms..but we dont know the renormalized masses accurately since we can only calculate the propagator corrections only to first few orders at best...also the counterterms sort of soak up the cutoff dependence of the mass, then how come it still remains a renormalized mass (dependent on cutoff)? I am really confused about this whole business.