Variational Cumulant Expansion Study of Z(N) Lattice Gauge Theory with Symanzik's Improved Action

摘要

With the variation cumulate expansion (VCE) method, the internal energy and the specific heat of the Z(N) lattice gauge theory with Symanzik's improved action are calculated up to the third order. The variational parameter is determined by the main valued method and the result is compared with the VCE result for standard Wilson action. Furthermore, the changes are compared with those of the SU(2) case.