2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/178769We report on the non-perturbative computation of the running coupling of two-flavour QCD in the Schr"odinger functional scheme. The corresponding Lambda-parameter, which describes the coupling strength at high energy, is related to a low energy scale which still remains to be connected to a hadronic ``experimentally'' observable quantity. We find the non-perturbative evolution of the coupling indispensable to avoid untolerable errors in the estimated Lambda-parameter.14 pages, 5 figures, 3 tables, some changes in the data analysis after discovery and correction of an error in Nucl. Phys. B 525, 387 (1998) by C. Christou et al. (hep-lat/9801007v2, Erratum to appear)High Energy Physics - LatticeHigh Energy Physics - PhenomenologyFirst results on the running coupling in QCD with two massless flavourstext