- #1
Wledig
- 69
- 1
I was reading about the renormalization of ##\phi^4## theory and it was mentioned that in order to renormalize the 2-point function ##\Gamma^{(2)}(p)## we add the counterterm :
[tex]\delta \mathcal{L}_1 = -\dfrac{gm^2}{32\pi \epsilon^2}\phi^2[/tex]
to the Lagrangian, which should give rise to a propagator term of the form:
[tex]-\dfrac{igm^2}{16\pi^2 \epsilon}[/tex]
that will cancel the divergent term in ##\Gamma^{(2)}(p)##. My problem is with the expression above, it's unclear to me how to reach this propagator correction just from the Lagrangian. How can this be achieved?
[tex]\delta \mathcal{L}_1 = -\dfrac{gm^2}{32\pi \epsilon^2}\phi^2[/tex]
to the Lagrangian, which should give rise to a propagator term of the form:
[tex]-\dfrac{igm^2}{16\pi^2 \epsilon}[/tex]
that will cancel the divergent term in ##\Gamma^{(2)}(p)##. My problem is with the expression above, it's unclear to me how to reach this propagator correction just from the Lagrangian. How can this be achieved?