NONLINEAR σ-MODEL ON MULTIDIMENSIONAL CURVED SPACE WITH CERTAIN CYLINDRICAL SYMMETRY
A dual transformation is found for a class of nonlinear σ-model defined on a multidimensional curved space with cylindrical symmetry. The system is invariant under proper combination of the dual transformation and the general coordinate transformation. An infinite number of nonlocal conservation laws as well as the Kac-Moody algebra follow directly from the dual transformation. A Bäcklund transformation that generates new solutions from a given one can also be constructed.