Four point functions in Keldysh basis

May, 2001
27 pages
e-Print:
Report number:
  • INLN-2001-12

Citations per year

1998200320082013201810
Abstract:
The Keldysh three- and four-point functions are related to analytical continuations of the Imaginary Time amplitudes,in momentum space. The relation provides an interesting interpretation of the amplitudes that are specific to the Keldysh basis, and of the Ward Identities they satisfy in QED. The interpretation carries over to the (perturbative) non-equilibrium case.
  • field theory: finite temperature
  • quantum electrodynamics
  • propagator
  • vertex function
  • n-point function: 4
  • analytic properties
  • Ward identity
  • Feynman graph