A Deduced Feynman Rule for Calculating Retarded and Advanced Green Function in Closed Time Path Formalism
- Received Date: 2003-07-18
- Accepted Date: 1900-01-01
- Available Online: 2004-07-05
Abstract: Based on the closed time path formalism, a deduced Feynman rule for directly calculating the retarded and advanced Green functions is given. This Feynman rule is used to calculate the two-point self-energy and three-point vertex correction in φ3 theory. The generalized fluctuation-dissipation theorem for three-point nonlinear response function is verified.