Strong Coupling

Abstract
For the case of the charged scalar theory a class of rigorous transformations is described which brings into explicit evidence the dependence of the Hamiltonian on the charge of the system. These transformations are noncanonical, nonadiabatic, and nonlinear. The strong-coupling Hamiltonian is obtained as a special case and is given in closed form. It is shown that in static approximation there exist bound states for arbitrarily high value of the charge of the isobar. The validity of the expansion method dealing with nonstatic effects is discussed, and it is shown that the usual strong-coupled procedure at best has meaning only for finite source size. The definition of nucleon-one meson states in the presence of finite isobar level separations is treated.