Phase transition with an infinite number of order parameters in the U(∞) lattice gauge theory
Kazakov V. A., Kozhamkulov T. A., Migdal A. A.
The U (Ν) lattice gauge theory identifies N gauge-invariant parameters in the limit iV-^oo. These parameters describe the phase transition from the strong-coupling region to the weak-coupling region. A strong-coupling-expansion method is used to calculate the effective potential of the theory in terms of these parameters. A single-placquet model and a second-order expansion for a Z>-dimensional gauge theory are used to test the effectiveness of the method.