FINITE-SIZE-SCALING AND UNIVERSALITY ABOVE THE UPPER CRITICAL DIMENSIONALITY

According to renormalization theory, Ising systems above their upper c ritical dimensionality d(u) = 4 have classical critical behavior and t he ratio of magnetization moments Q = [m(2)]2/[m(4)]) has the universa l value 0.456947.... However, Monte Carlo simulations of d = 5 Ising m odels have been reported which yield strikingly different results, sug gesting that the renormalization scenario is incorrect. We investigate this issue by simulation of a more general model in which d(u) < 4, a nd a careful analysis of the corrections to scaling. Our results are i n perfect agreement with the renormalization theory and provide an exp lanation of the discrepancy mentioned.