Two-loop Terms Research Articles

String model potentials and lattice gauge theories

The static potentials from bosonic string models are examined to the two-loop level. Available MC data for 4-dimensional SU(3) are in approximate agreement with the universal leading order predictions but fail to reproduce the Nambu string when the two-loop terms are included in the analysis. We also confront Nambu string model predictions for T c σ with SU(2), SU(3) and SU( N → ∞) MC data. In the SU(2) case, impressive agreement is found both in 3 and 4 dimensions. In contrast, the data for SU(3) and SU( N → ∞) differ from the string model prediction. These theories have identical values for T c σ , indicating that N → ∞ is a good approximation to N = 3.