  The dual formulation of the compact U(1) lattice gauge theory in three
spacetime dimensions allows to finely study the squared width and the profile
of the confining flux tube on a wide range of physical interquark distances.
The results obtained in Monte Carlo simulations are compared with the
predictions of the effective bosonic-string model and with the dual
superconductor model. While the former fails at describing the data from a
quantitative point of view, the latter is in good agreement with it. An
interpretation of these results is proposed in light of the particular features
of the U(1) lattice gauge theory in 3D and a comparison with non-Abelian gauge
theories in four spacetime dimensions is discussed.
