Nonlinear Electromagnetic Self-Duality and Legendre Transformations
arXiv:hep-th/9712103
Abstract
We discuss continuous duality transformations and the properties of classical theories with invariant interactions between electromagnetic fields and matter. The case of scalar fields is treated in some detail. Special discrete elements of the continuous group are shown to be related to the Legendre transformation with respect to the field strengths.
17 pages, full postscript available from http://theor1.lbl.gov/www/theorygroup/papers/41110.ps