k-strings and baryon vertices in SU(N) gauge theories

Abstract

It is pointed out that the sine law for the k-string tension emerges as the critical threshold below which the spatial Z_N symmetry of the static baryon potential is spontaneously broken. This result applies not only to SU(N) gauge theories, but to any gauge system with stable k-strings admitting a baryon vertex made with N sources in the fundamental representation. Some simple examples are worked out.

Comments: 4 pages, 4 figures, v2: reference added, v3: comments and references added