I know the electron-photon interaction Lagrangian from QED: ($-ie\bar{\Psi}\gamma^{\mu}A_{\mu}\Psi$). However, this interaction seems to describe the interaction of electron and positron with a photon (thus there is a $\bar{\Psi}$ for positron). This makes sense when an electron radiates a virtual photon (and becomes a positron) and then reabsorbs the photon again (and becomes an electron again). What about the case when an electron emits a real photon (and never becomes a positron) like the case of synchrotron radiation? What is the Lagrangian in that case since we wouldn't have any electron-positron vertex?
Subscribe to:
Post Comments (Atom)
-
In the crystal, infinitesimal translational symmetry breaking makes the phonon, In ferromagnet, time-reversal symmetry breaking makes magnon...
-
A "Schrödinger's cat state" is a macroscopic superposition state. Quantum states can interfere in simple experiments (such as ...
-
The degeneracy for an $p$-dimensional quantum harmonic oscillator is given by [ 1 ] as $$g(n,p) = \frac{(n+p-1)!}{n!(p-1)!}$$ The $g$ is the...
No comments:
Post a Comment