An algebraic characterization of the Korteweg-de Vries hierarchy
The paper aims to explore the algebraic characteristic property of the Korteweg-de Vries hierarchy. It is shown that the conserved differential polynomials of the Korteweg-de Vries equation \[ u_t=u_{xxx}-12uu_x \] are those with vanishing residues evaluated on the formal power series of the kind \[ u=x^{-2}+u_0+\sum_{n\geq 2}u_nx^n. \] The result reflects the enigmatical university that distinguishes the Sato bilinear identity in soliton theory.
scientific article; zbMATH DE number 1820821