LAMBDA(2)-CONTRIBUTION TO THE CONDENSATE IN LATTICE GAUGE-THEORY

We present some evidence that in lattice gauge theory the condensate c ontains a non-perturbative contribution proportional to Lambda(2), the square of the physical scale. This result is based on an analysis of the Wilson loop plaquette expectation from Monte Carlo simulations and its perturbative expansion computed to eight loops. The analysis is n ot fully conclusive since the calculations are done on a finite lattic e and one needs an extrapolation to infinite lattice. It has been rece ntly suggested that in the gluon condensate a Lambda(2)-contribution c ould be present coming from the large momentum behaviour of the runnin g coupling and not connected to operator product expansion. (C) 1998 P ublished by Elsevier Science B.V.