Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

In QFT, specifically in scattering processes, what is the physical significance of the poles / residues of the $N$-point correlation function? And why?

share|cite|improve this question
Related: – Qmechanic Apr 27 '13 at 18:54

In the frequency domain, poles of the correlation function $G^{r}(\omega)$ correspond to resonance frequencies. In many body theory, such resonances describe metastable oscillations relating to quasi-particles characterized by self-energies.

share|cite|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.