C. Rogers et Wk. Schief, INTRINSIC GEOMETRY OF THE NLS EQUATION AND ITS AUTO-BACKLUND TRANSFORMATION, Studies in applied mathematics, 101(3), 1998, pp. 267-287
The nonlinear Schrodinger equation is derived in a general intrinsic g
eometric setting involving a normal congruence originally investigated
by Marris and Passman in 1969 in a hydrodynamical context. Geometric
properties of members of the normal congruence are adduced and an intr
insic representation of the auto-Backlund transformation is obtained f
or the nonlinear Schrodinger equation.