effective string tension out to at distances of at least $r \simeq 1.6/ \sqrt{K}$, suggesting that if there are any vortices they are not encoded in the monopole fields.

PACS indices: 11.15.Ha, 12.38.Aw, 14.80.Hv.

Introduction {#sec_intro}
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Many recent efforts to elucidate the mechanism of confinement in [qcd]{} and non–Abelian gauge theories have focused on isolating a reduced set of variables that are responsible for the confining behaviour. In the dual superconducting vacuum hypothesis [@mandelstam76; @thooft81] the crucial degrees of freedom are the magnetic monopoles revealed after Abelian projection. In the maximally Abelian gauge [@thooft81; @kronfeld87] one finds that the extracted U(1) fields possess a string tension that approximately equals the original SU(2) string tension (‘Abelian dominance’) [@suzuki90], and that this is almost entirely due to monopole currents in these Abelian fields (‘monopole dominance’) [@stack94; @bali96]. The magnetic currents observed in the maximally Abelian gauge are found to have non-trivial correlations with gauge-invariant quantities such as the action and topological charge densities (see for example [@feurstein97; @bakker98] and references therein) and this invites the hypothesis that the structures formed by the magnetic monopoles correspond to similar objects in the SU(2) vacuum, seen after gauge fixing and Abelian projection. If the 