Quote:
|
Originally Posted by Sylas
Quote:
|
Originally Posted by Fortis
I'll try to say something a little more coherent later on, but if you want,you can have a quick look at this page.  |
Thanks... also useful is the link I gave above from SLAC; though it does not mention polarization. A virtual photon can have mass, apparently; and I think this may be associated with the possibility of strange polarizations. Does that makes sense? I'm just starting out on this, however. |
IIRC that's pretty much the case. In fact as well as the two transverse polarisations and the longitudinal polarisation, virtual photons can also be scalar (if you imagine the polarisation as a vector, the transverse polarisations are in the x, and y directions, the longitudinal polarisation is in the z direction, and the scalar one is polarised in the t direction, if that makes sense
.)
I've been looking for an on-line text that deals with this (and somewhat more elegantly than I, particularly as I'm a little rusty
), and the best page that I have found is
this one which more or less covers the same stuff as Mandl and Shaw. (If you want another book on QFT that takes a different approach, I'd recommend Quantum and Statistical Field Theory by Michel Le Bellac, which motivates a lot of the formalism, including the RG, from a statistical physics starting point.)
Quote:
|
Your reference is especially relevant for this thread, since right at the start it speaks of the emission of a photon by an electron, and explains that this is impossible due to the requirements of energy momentum conservation. Deja vu!
|
Yup, it's deja vu all over again.
(Many thanks to Yogi Berra for that one.)