Existence of solutions to non-homogeneous higher order differential equation in the Schwartz space

Abstract: There is studied problem on existence of solutions to non-homogeneous differential equation of higher even order. Similar problem arises while studying soliton and soliton-like solutions to partial differential equations of integrable type. By means of Fourier transform and theory of pseudodifferential operators there is proved the theorem on necessary and sufficient conditions on existence of solutions to linear non-homogeneous differential equation of higher even order in the Schwartz space.