An effective action for spacelike links is given in this paper. Using this action, we can obtain the effective spin model by the variational cumulant expansion method. The study of the critical coupling for the SU(2) case shows that quite accurate results can be obtained. We expect that this approach may open an avenue for the investigation of the deconfining phase transition for large $N_{\tau }$ lattices.

• Received 9 November 1992

DOI:https://doi.org/10.1103/PhysRevD.48.397