出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We discuss the status of different determinations of as, motivating a precise and reliable computation from lattice QCD. In order to suppress perturbative errors, the non-perturbative computation has to reach high energy scales m. Such results already exist in the SF-scheme for Nf = 0;2 [1, 2] and Nf = 3 [3]. We recently added the running with four massless flavours in a range of a from about 0.07 to 0.3 . It is based on our recent determination of the Sheikholeslami Wohlert coefficient in the four-flavour theory.
