GEOMETRIC ASPECTS OF CONFINING STRINGS

Confining strings in 4D are effective, thick strings describing the co nfinement phase of compact U(1) and, possibly, also non-Abelian gauge fields. We show that these strings are dual to the gauge fields, inasm uch their perturbative regime corresponds to the strong coupling (e >> 1) regime of the gauge theory. In this regime they describe smooth su rfaces with long-range correlations and Hausdorff dimension two. For l ower couplings e and monopole fugacities z, a phase transition takes p lace, beyond which the smooth string picture is lost. On the critical line intrinsic distances on the surface diverge and correlators vanish , indicating that world-sheets become fractal. (C) 1998 Elsevier Scien ce B.V.