STRONG-COUPLING LATTICE SCHWINGER MODEL ON LARGE SPHERELIKE LATTICES

The lattice regularized Schwinger model for one fermion flavor and in the strong coupling limit is studied through its equivalent representa tion as a restricted 8-vertex model. The Monte Carlo simulation on lat tices with torus topology is handicapped by a severe non-ergodicity of the updating algorithm; introducing lattices with spherelike topology avoids this problem. We present a large scale study leading to the id entification of a critical point with critical exponent nu = 1, in the universality class of the Ising model or, equivalently, the lattice m odel of free fermions.