出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：K strings in Yang-Mills theory can be considered as bound states of k elementary conning strings
carrying one unit of colour ux. Current estimates of k-string tension sk are very sensitive to
the leading corrections due to quantum uctuations of the string. In this study we address this
problem by comparing Polyakov-Polyakov correlators in the fundamental representation (k = 1)
with the corresponding ones with k = 2 in the conning phase of a Z4 gauge theory in three
dimensions. Highly efcient simulation techniques are available in this case. Although the k = 1
Polyakov-Polyakov correlator matches nicely with the expected bosonic string effects up to the
Next-to-Leading-Order, the k = 2 Polyakov-Polyakov correlators show large deviations. This is
an important source of potential systematic errors in the current estimates of sk.
