出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We consider whether the 1/N corrections to k-string tensions must begin at order 1/N2; as in;the Sine Law; or whether odd powers of 1/N; as in Casimir Scaling; are also acceptable. The;issue is important because different models of confinement differ in their predictions for the;representation-dependence of k-string tensions; and corrections involving odd powers of 1/N;would seem to be ruled out by the large-N expansion. We show; however; that k-string tensions;may; in fact; have leading 1/N corrections; and consistency with the large-N expansion; in the;open string sector; is achieved by an exact pairwise cancellation among terms involving odd powers;of 1/N in particular combinations of Wilson loops. It is shown how these cancellations come;about in a concrete example; namely; strong coupling lattice gauge theory with the heat-kernel;action; in which k-string tensions follow the Casimir scaling rule.
