We give divisibility results for the (global) characteristic varieties of
hypersurface complements expressed in terms of the local characteristic
varieties at points along one of the irreducible components of the
hypersurface. As an application, we recast old and obtain new finiteness and
divisibility results for the classical (infinite cyclic) Alexander modules of
complex hypersurface complements. Moreover, for the special case of hyperplane
arrangements, we translate our divisibility results for characteristic
varieties in terms of the corresponding resonance varieties.Comment: v2: much of the paper has been re-written, including a more detailed
introduction and updated reference