2012 年 119 巻 4C 号 p. F11-F13
Two-particle irreducible effective action provides a useful framework to perform non-perturbative analyses in field theory. Here we report its application to the evaluation of the static critical exponents of O(N) scalar theory, and discuss a possible way to obtain the spectral function and to study dynamic criticality of the Nambu-Jona-Lasinio model.