this was a mistake in writing. I was only meaning that "I have some idea of what is a "virtual" particle in perturbative QFT" and only in perturbative QFT because I think this is an artefact of perturbative approximation of quantum mecanics.
But, if you can proove the...
I have not looked at Path integrals from so long time...
I think one of the approach of Path Integral is to consider it as a Wiener Integral with a Wiener process. So in some way, it can be related to random walk where you can expect very strange path happening, they are just unfavored...
I think if you describe the wave by a cos(px - Et + phi) then you violate the relativity principle (the classical one from Galilei).
If for one observer the wave cancels every L = pi/p
For a second observer at speed V wrt the first, the wave cancels every L = pi/p' with p' = p + mV.
I think there are two issues with the wavefunctions collapse :
- the mathematical formalism which I have no problem to accept
- the physical interpretation which is subject to many interpretations
Why such assertion ? Is it physics or metaphysics ?
I do not understand why the helicity of the neutrino should be invariant now it has a mass ?
Indeed if neutrinos have mass, it just implies that LH and RH chirality states are no more solutions of Weyl equations and so are no more eigenvalues of helicity operator.
Which means we...