Nonlocal pseudosymmetries and Bäcklund transformations as -morphisms
arXiv:2506.01932 · doi:10.1016/j.jde.2026.114334
Abstract
In this paper, we show how factorisation with respect to nonlocal pseudosymmetries allows one to obtain Bäcklund transformations, interpreted as nonlocal -morphisms of differential equations. According to this approach, which is illustrated through several examples, the Bäcklund transformations are determined by basic invariants of the exploited nonlocal pseudosymmetries.
Published Open Access in J. Differential Equations. This version replaces the previous preprint and includes all final corrections. Please cite and access the official version at https://doi.org/10.1016/j.jde.2026.114334