2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/53765The Laughlin function of quantum Hall effect is shown to satisfy Hirota's bilinear difference equation with certain coefficients a little different from the KP hierarchy. Vertex operators which constitute blocks of solutions generate a Bäcklund transformation. Besides the Laughlin function, the equation admits soliton solutions.Latex 11pages(LaTeX) TMUP-HEL-9311High Energy Physics - Theorytext