We study the different phases of field theories of compact antisymmetr
ic tensors of rank h - 1 in arbitrary space-time dimensions D = d + 1.
Starting in a 'Coulomb' phase, topological defects of dimension d - h
- 1 ((d - h - 1)-branes) may condense leading to a generalized 'confi
nement' phase. If the dual theory is also compact the model may also h
ave a third, generalized 'Higgs' phase, driven by the condensation of
the dual (h - 2)-branes. Developing on the work of Julia and Toulouse
for ordered solid-state media, we obtain the low-energy effective acti
on for these phases. Each phase has two dual descriptions in terms of
antisymmetric tensors of different ranks, which are massless for the C
oulomb phase but massive for the Higgs and confinement phases. We illu
strate our prescription in detail for compact QED in 4D, Compact QED a
nd O(2) models in 3D, as well as a periodic scalar field in 2D (string
s on a circle), are also discussed. In this last case we show how T-du
ality is maintained if one considers both world-sheet instantons and t
heir duals. We also unify various approaches to the problem of the axi
on mass in 4D string models. Finally we discuss possible implications
of our results for non-perturbative issues in string theory. (C) 1997
Elsevier Science B.V.