The geometric properties of the critical fluctuations in Abelian gauge theo
ries such as the Ginzburg-Landau model are analyzed in zero background fiel
d. Using a dual description, we obtain scaling relations between exponents
of geometric and thermodynamic nature. In particular, we connect the anomal
ous scaling dimension eta of the dual matter field to the Hausdorff dimensi
on D-H Of the critical fluctuations, which are fractal objects. The connect
ion between the values of eta and D-H, and the possibility of having a ther
modynamic transition in finite background field, is discussed.